Abstract

In the Japanese philosophy of life, ‘ikigai’ broadly refers to having a ‘reason for living’, or a purpose in life. From a phenomenological and empirical viewpoint, ikigai is reported to increase human well-being and even life expectancy. However, it remains difficult to translate, define and formalize with regard to contemporary psychological theories. In this respect, the aim of this paper is twofold: to capture as accurately as possible what ikigai is, and to examine whether the concept applies to a professional context. We first offer a comprehensive overview of ikigai, bridge the gap between this specific body of literature and related psychological theoretical frameworks, such as those addressing motivation, well-being, and attention. On this basis, we conceptualize an integrated cognitive-motivational model of ikigai using an IPO (Input-Process-Output) framework: we organize dispositional or situational factors supposedly supporting ikigai as inputs, fueling the core process of ikigai (mainly built from motivational and attentional mechanisms), which produce outcomes (including well-being). A feedback loop completes the model and allows the process to maintain over time. This conceptual proposal is a first step towards applying and testing the model in professional contexts, in order to renew our approach of engagement, well-being, and performance at work as well as inspire workplace evolution.

Overview & Summary

This paper addresses the Japanese concept of ikigai—broadly translated as "a reason for living" or a sense that "life is worth living"—and seeks to formalize it within modern psychological literature to evaluate its applicability to the workplace. Although empirical research in Japan connects ikigai to increased psychological well-being, better health, and reduced all-cause mortality, the concept lacks a consensual academic definition and a formalized cognitive model.

To bridge this gap, the authors synthesize cross-cultural literature and psychological theories—specifically Self-Determination Theory (SDT), Mindfulness, and Seligman’s PERMA framework—to construct an Integrated Cognitive-Motivational Model of Ikigai using an Input-Process-Output (IPO) framework with a continuous feedback loop.

Cultural Context and Evolution of Ikigai Concepts

Cultural Specificities

• Sociocentric vs. Individualistic Selves: The Japanese self tends to be socio-centric, contextual, interdependent, and aligned with collectivist values. In contrast, Western (especially North American) views prioritize individualism, autonomy, and personal distinction.

• Interpretation of Needs: Collectivist cultures emphasize contribution to the group, social hierarchy, and relational harmony, whereas individualist cultures focus on personal desires, self-reliance, and individual accomplishment.

Japanese Conceptualizations

• Kamiya’s Framework (1966): Identified seven universal needs that ikigai satisfies:

• Survival

• Growth and Change

• Future orientation (goals and dreams)

• Influence (feeling necessary to others)

• Freedom of choice

• Self-fulfillment/personal development

• Meaning of life (a sense of personal value and worth)

• Kumano’s Hierarchical Model (2006, 2012): Identified four central psychological states (Life-affirmation, Meaning of life, Life fulfillment, and Existential value) and five value-laden cognitive mechanisms (making sense of the past, setting future goals, being absorbed in the positive present, accepting negative situations, and coping with negative situations). Kumano placed subjective well-being and quality of life as peripheral rather than central to ikigai.

Western/Popular View (Winn’s Diagram)

• Developed as an adaptation of Andrés Zuzunaga’s "Purpose Venn Diagram" combined with Dan Buettner’s TED talk on Okinawan longevity.

• Represents ikigai as the intersection of four domains:

• What you love

• What you are good at

• What you are paid for

• What the world needs

• Strengths: Synthesizes internal personal desires, external financial rewards, and altruistic impact.

• Limitations: The inclusion of economic compensation ("what you are paid for") is debated; classical Japanese ikigai operates independently of financial rewards and can be found in family, hobbies, or community roles.

The Integrated Cognitive-Motivational Model (IPO Framework)

The authors model ikigai as a dynamic cognitive-motivational system using an Input-Process-Output (IPO) structure connected by a continuous feedback mechanism.

1. Inputs (Antecedents & Context)

Inputs consist of the dispositional traits and situational conditions required to initiate and foster the ikigai core processes:

• Situational Factors (Work Environment):

• Social & Physical Environment: Job content, organizational climate, workspace ergonomics, communication dynamics, and physical working conditions.

• Job Characteristics: Task variety, task identity, significance, autonomy, and feedback (per Hackman & Oldham) shift the perceived locus of causality inward, enhancing self-determination.

• Dispositional Factors (Individual Differences):

• Causality Orientation: Stable individual traits regarding motivational orientation (intrinsic vs. controlled/extrinsic) that influence how individuals interpret workplace tasks and environment.

2. Core Processes (Intrapersonal Mechanisms)

The engine of ikigai integrates motivational regulation and attentional processing:

• Self-Determination Theory (SDT): Fulfills three basic psychological needs:

• Competence: Feeling effective and capable.

• Autonomy: Feeling like the origin of one's actions.

• Relatedness: Feeling connected to and valued by others (strongly aligned with the sociocentric aspect of ikigai).

• Motivational Continuum: Spans from external regulation to intrinsic regulation. While traditional SDT sees intrinsic motivation as the ultimate goal, ikigai elevates identified and integrated regulations—doing things because they align with deeply held values or benefit society ("what the world needs").

• Mindfulness:

• Defined as nonjudgmental, open present-moment awareness.

• Serves as a wide, receptive attentional filter that balances self-interest with prosocial, altruistic goals (self-transcendence).

• Helps individuals align daily actions with core existential values.

3. Outputs (Observable & Internal Outcomes)

• Well-Being (Psychological & Subjective): Framed using Seligman’s PERMA model:

• Positive Emotions (P)

• Engagement (E)

• Relationships (R)

• Meaning (M)

• Accomplishment (A)

• Eudaimonic well-being (meaning, self-acceptance) is prioritized as a primary output over short-term hedonic pleasure.

• Physical Health & Longevity: Supported by empirical data linking strong ikigai to reduced cardiovascular/all-cause mortality and overall health maintenance.

• Workplace Performance: Proposed as a direct output resulting from enhanced intrinsic motivation, optimal engagement, and present-moment attentional focus.

4. Feedback Loop (Commitment Process)

• Behaviors and positive outputs reinforce psychological commitment (Kiesler & Sakumura).

• A continuous commitment loop feeds back into the core processes, sustaining ikigai as a self-maintaining, lifelong dynamic state.

Key Applications, Limitations, and Future Directions

• Workplace Design & Industry 4.0/5.0: The model offers a practical framework to design jobs, organizational management practices, and technological tools (including robotics in industrial/railway maintenance contexts) that satisfy workers' psychological needs, foster meaning, and promote well-being alongside productivity.

• Cultural Portability: Translating a socio-centric Japanese life philosophy to Western corporate settings presents challenges, particularly around navigating extrinsic rewards vs. intrinsic/altruistic values.

We march to the beat of an invisible metronome, ticking somewhere behind the sternum, counting out a rhythm none of us remember agreeing to keep. Modern life has become an exercise in optimization: the sanitized diet, the safety-rated car, the sleep tracked to the minute, the inbox cleared by nine. Each of these habits, taken alone, is perfectly reasonable — the diet does lower cholesterol, the car really does survive the crash test better than its predecessor. Somewhere in the accumulation, though, the metronome stops keeping time for a life and starts replacing one. You can be fitter, safer, more efficient, and still wake up feeling like an animal that has memorized every rule of a cage without ever noticing the bars.

This training starts early, in the glittering, unforgiving arena of adolescence, where a teenager learns — usually without a single word spoken aloud — that belonging is not a gift but something won through leverage. You are taught, by the sheer weight of example around you, to price your own worth in the currency of popularity: who sat where at lunch, whose attention you could hold, whose approval counted and whose didn't. Nobody sits a fourteen-year-old down and explains the exchange rate. It's simply the only economy visible from inside a school hallway, and children learn the rules of the room they happen to be standing in, the same as everyone else who has ever stood in a room.

That economy has a long afterlife. Long after the hallway, we go on lending our sense of what's possible to people we'll never meet — building whole private relationships with public figures, borrowing their apparent immunity to ordinary indignity, right up until some fact intrudes and the borrowed armor turns out to have been cardboard the whole time. What stings in that moment isn't really disillusionment with them. It's the quiet admission that we'd handed someone else the job of proving a flawless life was achievable, and they were never going to be able to do it, because nobody can.

To step off that pedestal is to reclaim the strange, private authority of thinking for yourself — deciding, on your own evidence, what a good life actually contains, rather than importing the answer from whichever feed happened to reach you first. This is harder than it sounds, because the assembly line never announces itself as a trend while you're standing on it. From the inside it feels like taste. It feels like your own idea. You tend to recognize the machine only once you've stepped far enough back to see its outline.

Which is only the first half of the work, and the easier half. You can unfollow an account. Turning that same attention inward, toward the harder question of whether you actually know the person you've been so busy defending from the crowd, is another matter entirely.

Most of us walk through decades of our own lives less like owners than like long-term houseguests — familiar with the furniture, ignorant of what's behind the walls. Ask people what they want and they'll answer fluently, sometimes beautifully. Watch what they actually choose, over and over, and a different portrait emerges, one they'd often fail to recognize. The friend who says she wants calm, and finds herself, with a kind of dazed regularity, in the company of people who keep her in a low-grade state of emergency. The man who insists, quite sincerely, that nothing is wrong, while closing every cupboard door in the kitchen half a second harder than the task requires.

Call it a gap, not a lie: between the self we've been told we are — reasonable, easygoing, over it — and the self actually operating the machinery of our choices. Closing that gap is uncomfortable, and the people around us rarely help. We're coddled by a soft wall of silence, built by friends who understand, correctly, that naming a pattern out loud is a poor way to enjoy a pleasant dinner. So they let it go. We let it go. The pattern repeats a third time, a fifth, a tenth, each one arriving dressed as fresh coincidence rather than what it actually is: information, delivered late.

The most reliable way to find out who you are isn't to meditate on the question in the abstract. It's to examine your own behavior with the same detached curiosity you'd bring to a stranger's — not *what did I intend*, but *what did I actually do*, three separate times, in three separate rooms. Patterns that survive three repetitions are rarely accidents. They tend to be the oldest, least examined architecture of the self, laid down long before you had any say in the blueprint, and still quietly running the building.

A cruder but more honest version of the same exercise is just keeping score — not of feelings, which lie fluently, but of choices, on the ordinary days when nobody was watching closely enough to require an explanation of yourself. Someone who wants to know whether they're actually as generous as they believe doesn't need a course in self-inquiry. They need three months of noticing, plainly, what they did the moment generosity would have cost them something. The self shows up more reliably in its margins than in its declarations.

It helps, too, to ask the people who love you what they've noticed, and then to actually listen to the answer instead of assembling your defense while they're still talking. The friend who tells you, gently, that you always seem to leave right when things get good is handing you a piece of yourself you can't see from the inside. There's a cost to refusing that, and it compounds quietly, the way most costs worth worrying about do.

Some of this work can be overdone — turned inward not to find clarity but to postpone acting on it indefinitely, analysis standing in for the harder business of change. But that's a smaller risk, in practice, than the opposite one: never doing the audit at all, and paying, again and again, for pain that a little honest bookkeeping would have flagged the second time around.

When two people fall in love, what they're really doing, whether they know it or not, is placing an enormous bet with almost no information. Two blind gamblers leaping together into a future neither can see. It's tempting to believe the bet gets placed in pursuit of joy — that we scan a room for the person most likely to make us happy and choose accordingly. Long before we're conscious of doing it, though, most of us are scanning for the familiar, and familiar is a much stranger, much less flattering criterion than happy.

The nervous system reads familiarity as safety, even when what's familiar is chaos. Someone raised by a parent whose love arrived unpredictably — warm one night, cold and cutting the next — often grows into an adult who finds steady, uneventful affection faintly suspicious, even boring, the way ears accustomed to loud music find silence unsettling instead of restful. Calm doesn't register as safety to that person. It registers as the ten seconds before something goes wrong. So without ever deciding to, they find the unavailable partner more compelling than the reliable one — not despite the unavailability but because of it, because somewhere in the oldest, least examined part of the self, it's simply what home has always felt like.

That said, it would be too tidy to file every difficult relationship under old trauma wearing a new face. Some people who are genuinely hard to love are also genuinely worth the difficulty, complicated in ways that reward patience rather than punish it. The trick is telling the difference between choosing a complex person and compulsively choosing a wound — a distinction that's easy to romanticize and much harder to actually make from inside the relationship, where the electric familiarity of old pain can pass, convincingly, for depth.

Underneath all of this sits a plainer fact: we are, every one of us, fundamentally strange. Not as an insult — as an honest description of what a person is up close, a tangle of contradictory needs and inherited fears and private rules never spoken aloud, drifting through the world with considerably less self-knowledge than our confident tone of voice would suggest. Two such creatures decide to build a life together, each one mysterious even to themselves. That it goes wrong sometimes is not the surprising part. The surprising part is that it ever goes right at all.

The couples who last are rarely the ones who found some rare frictionless match. They're the ones who stopped being surprised by the friction and built something sturdy enough to hold it anyway — which suggests that if the compass itself was calibrated in childhood, long before anyone had a vote, the only real leverage left is not in who we're drawn to but in what we do with them once we've arrived. That, unlike attraction, is a skill. Like every skill, it can be practiced badly or well.

Picture an ordinary Tuesday dinner. One partner has cooked, a little too much salt in the sauce, nothing catastrophic, and the other, tired from a day that had nothing to do with dinner, says nothing about the salt but goes quiet in a specific way — not the quiet of contentment, the quiet of a held breath. Almost everyone recognizes this moment. Almost no one, asked in the moment, could explain what it's actually for.

The sulk is a demand wearing an absence as a disguise. It says, without saying it: you should already know what's wrong, and if I have to tell you, the telling itself proves you don't really know me. Somewhere underneath it is the old, infant hope of being loved wordlessly, instantly, by someone who reads the need before it's named — a beautiful expectation, and one that has no real place in an adult relationship, where the person across the table is not a devoted parent scanning your every gesture but a separate, tired, distracted human being running their own inner weather.

What the sulk avoids is the plainer, less flattering sentence: the sauce was too salty, but that's not actually what's bothering me — I've had a hard week and wanted to feel taken care of tonight. That sentence costs something. It risks sounding petty, or needy, or simply wrong about your own feelings. The sulk costs more, just more slowly — an evening, or a marriage, spent at the same table by two people both wanting to be understood and neither willing to be the one who explains.

Most of the harder work of loving someone happens in exactly this kind of moment, and it's mostly a matter of which story you reach for. This is who they really are, one story says, and I've made a terrible mistake. This is a person I love, having a bad hour, says the other, and bad hours are not verdicts. People who are good at long relationships aren't people who never reach for the first story. They're people who've gotten quicker at catching themselves and reaching for the second one instead — the patient teacher's version of events rather than the frightened accuser's.

None of which means every private irritation needs narrating in real time. Some discretion is simply kindness, and a household where every passing thought gets spoken aloud can wear a person out just as thoroughly as one where nothing gets said. The skill isn't confession. It's knowing which silences are rest and which ones are the sulk, dressed up to look like peace.

At a much lower volume, the same mechanism runs through nearly every relationship worth keeping — the friend who goes quiet after a canceled plan, the sibling who never quite says what's bothering them at the holiday table. Different room. Same held breath.

Beyond the small, high-stakes theater of romantic love lies the wider, gentler work of navigating everyone else — friends, acquaintances, the strangers we sit beside on long flights and never see again. The same principle applies at a lower voltage here: speak your own truths clearly, but spend more time listening than talking, because nearly everyone carries some piece of hard-won knowledge you don't have, even the people whose opinions bore you within the first five minutes. That's not the same as owing everyone your ongoing company, though. Some people, once you've heard them out, simply aren't worth the continuing cost — loud, aggrieved, allergic to any conversation that isn't about themselves — and steering your time away from them is triage, not cruelty.

When a friendship genuinely needs to end, the kindest version is rarely the gentlest-sounding one. A long, ambiguous fade — the unanswered text, the vague excuse, repeated for months — usually costs the other person more than a direct conversation would, because it makes them do the humiliating work of guessing on their own. Saying it plainly, once, without the theater of a farewell speech nobody asked for, tends to be the more respectful option, even though it feels like the harsher one in the moment.

The relationships people keep for decades rarely survive on magic. They survive on something closer to engineering: the repeated, unglamorous decision to accept a real, flawed, present person over the idea of a more perfect one who doesn't exist. A friend who's occasionally self-absorbed but has shown up at every real crisis of your adult life is worth more than a dozen more charming people who've never been tested. There's a real dignity in choosing good-enough-and-real over perfect-and-imagined — a dignity the soulmate myth tends to obscure, because it isn't only romantic love the myth distorts. It quietly convinces people to keep scanning for a more exciting friendship instead of tending the durable one already in front of them.

A few bonds are worth extraordinary effort precisely because of what they know about you that nobody new ever will. The friend who's known you since you were eleven carries a version of your history you've half-forgotten yourself — the version before the personality you perform now had fully hardened into place. Keeping that alive across widening gaps of geography and diverging lives takes real, unglamorous effort: the call you make even though you're tired, the visit you plan even though it's inconvenient. Past a certain age it rarely happens by accident. Siblings occupy an especially strange corner of this — not chosen, not always easy, but often the last people left who remember the same kitchen, the same arguments, the same childhood weather. When parents age and disappear, a sibling becomes one of the only remaining witnesses to a version of you that existed before you had to explain it to anyone.

So much of adult life, though, happens nowhere near the dinner table with old friends. It happens in the far less examined rooms where we work.

Ambition rarely announces its own motive. It's entirely possible to spend twenty years climbing toward a title, a salary, an office with a view, genuinely believing the whole time that the climb is simply about excellence — and to arrive at the summit only to find the fear you were climbing away from waiting there, unmoved, with better furniture around it. Plenty of driven people, to be fair, are doing exactly the work they love for exactly the reasons they think they are. Building something real — a company, a body of research, a skill practiced until it becomes art — is one of the more legitimate forms of self-expression a person has access to.

The harder question is which kind of ambition happens to be operating on any given day, and there's a fairly simple, mildly uncomfortable test for it: is the goal in front of you something you actually want, or something you want to be seen wanting? Does the promotion excite you because of what the work itself will let you build, or because of the relief you're imagining at finally getting to say the new title out loud at dinner? Both motives can run in the same career, sometimes in the same afternoon. When the second one quietly takes the wheel, though, achievements stop satisfying almost as soon as they arrive — status has no natural stopping point the way mastery does. There's always someone one rung higher, which means a ladder chosen for that reason never actually ends.

Money makes the confusion easiest to see, because money is genuinely useful — it buys real time, real safety, real distance from a certain low-grade dread — right up until it gets mistaken for the destination instead of the vehicle. Past a fairly modest threshold, more of it reliably fails to deliver what people expected it to deliver, and the pursuit continues anyway, because stopping would mean admitting the goalpost was never really about the money. It was about the fear underneath the money, the same fear ambition was supposed to have outrun by now.

There's a specific vertigo waiting for people who've let a job title do the work their identity should have been doing all along. It shows up most visibly at retirement, or after a layoff, when someone who's spent thirty years as the director, or the surgeon, or the founder, finds the silence where the title used to sit and isn't entirely sure who's left standing in it. Caring deeply about work isn't the problem. Letting the caring become the entire architecture of the self is — because nothing survives if the title is ever taken away, by choice or by circumstance or simply by time.

Work, at its best, is a use of the hours rather than merely a filling of them. But it's still only a use of the hours, and hours, unlike money, don't get recovered or renegotiated later. They pass, noticed or not, through a body that is doing exactly that: aging, quietly, underneath every meeting and every deadline.

There's a particular, almost embarrassing kind of vitality that belongs to a young body — the ability to stay up until four and feel merely tired rather than wrecked, to dance alone in an empty room because the music demanded it, to take the whole physical machine so completely for granted that its smooth running never once registers as a gift. This vitality is almost never recognized while it's actually happening. It tends to announce itself only in retrospect, usually right around when the knees begin sending their first quiet, complaining memos — and what had felt like a permanent condition turns out, all at once, to have been a season.

There's a case for spending some part of youth actually noticing this, rather than waiting for the knees to do the noticing for you. Not in a panicked, countdown-clock way, which tends to ruin the very thing it's trying to savor — more as a small, occasional discipline of attention, a moment taken now and then to feel the specific, finite pleasure of a body still doing everything asked of it without complaint.

Most of the anxious energy people spend worrying about the future turns out, in hindsight, to have been aimed at the wrong target. We rehearse disasters with detailed plots — the job loss we saw coming, the diagnosis we half-expected — and while some rehearsed fears do eventually show up, the ones that actually break people are usually the uninvited kind: the phone call on an unremarkable Tuesday afternoon, the ordinary day that turns out, only in hindsight, to have been the last ordinary day for a while. Prudence still has its place; preparing for what can reasonably be foreseen is simply sane. But it's worth remembering that the planning was never armor, only planning — and holding each calm, uneventful Tuesday with a little more gratitude than it usually gets, precisely because its calm was never guaranteed.

Aging brings its own specific, unglamorous griefs: prices that were once reasonable, politicians who once seemed competent, a decade that in memory gleams with a nobility it almost certainly didn't possess at the time. This is an old trick of the mind, the past quietly sanding down its own rough edges the longer we're away from it, and recognizing it as a trick rather than a fact is most of what it takes to stop falling for it.

Underneath a lot of this sits a habit, picked up early and rarely fully outgrown, of measuring your own trajectory against everyone else's — a comparison that turns out to be close to meaningless, since the race, if it's a race at all, is absurdly long and privately scored. Nobody else is running your particular course, with your particular knees, on your particular clock. The only real competitor who was ever on the track is the version of you from further back, who knew less, and who would very likely be relieved to see how far you've come.

Which brings us back to that invisible metronome from the beginning, the one counting out a rhythm none of us remember agreeing to keep. Its rhythm, by now, should look a little more specific: a status economy learned too early, a habit of measuring the self against other people's borrowed, unfinished lives, a nervous system that reads familiar pain as love, a fear of asking plainly for what we need. None of it is a personal failing so much as inherited weather — arriving mostly intact from childhoods nobody chose, running quietly underneath decisions that felt, at the time, entirely free.

The two blind gamblers turn out, on reflection, to describe more than just love. We choose careers, cities, whole identities with a fraction of the information a fully rational person would want, and then spend years finding out whether the bet paid off. It isn't a flaw specific to romance. It's what it is to be a creature that has to act before it fully understands — every creature, always.

Given all that, it would be reasonable to hope regret might be the exception in a well-lived life rather than the rule. It isn't. Regret behaves more like a tax than a symptom, charged on every path precisely because choosing one always means quietly closing the others. The person who marries will, on some private Tuesday years later, wonder about the life not chosen. The person who stays single does the same, in the other direction. Neither wondering is evidence that they chose wrong. It's evidence that they're human, which means getting exactly one version of a life that, from certain angles, could always have gone several other ways.

That doesn't erase the ache. It can change what the ache means, though — from proof of a mistake into something closer to the ordinary cost of having lived an actual, specific life instead of an abstract, unchosen one. There's real relief available in that difference, on the nights it matters.

There's also the houseguest to reckon with, the one from earlier who spent years politely tolerating the furniture of their own mind without ever opening the doors marked private. Self-knowledge, in the end, doesn't hand you a grander house. It hands you the keys to the one you were already living in — which turns out to be most of what it means to own a life rather than just occupy one: not more rooms, but the standing to walk through all of them, including the ones you'd been quietly avoiding.

What you didn't choose — the nervous system you were handed, the arena you first learned status in, the shape of love modeled for you before you had a vote — isn't a fair basis for holding yourself in contempt. A broken dream is not the same thing as a failed life, whatever it insists at two in the morning. What's left, the smaller and more workable thing, is how you meet your own difficulty when it shows up: with suspicion, the way the terrified accuser meets a partner's bad evening, or with something closer to the patient teacher's version of events — the generous read you'd extend, on a good day, to someone you actually loved.

Not a cure. There isn't one. Just a steadier way of carrying the whole strange, uncertain weight of it — as the owner of it now, rather than the guest — one ordinary Tuesday at a time, for as long as there are Tuesdays left.

Life, Information, and the Limits of Simulation

The Old Riddle of a Living Cosmos

Long before anyone had a word for biology, Aristotle imagined the entire cosmos as a single enormous organism, straining toward some final, built-in purpose — every falling stone, every growing tree, every orbiting sphere pulled forward by the same kind of directedness that pulls an acorn toward being an oak. This is teleology: the idea that things move not just because something pushed them, but because something is drawing them toward a destined end-state. Modern physics threw this idea out with real force. Newton's universe runs on push, not pull toward purpose; a falling apple has no goal, only a prior cause. And yet the question underneath Aristotle's picture never actually left. It just changed vocabulary. We no longer ask whether the heavens have intentions. We ask whether the universe computes — whether reality, at bottom, is an information-processing system, and whether life is simply what happens when that system's computations become sufficiently intricate.

This reframing is not merely a modern affectation. It matters because "computation" gives us something teleology never could: a mechanism. A goal is mysterious — what pulls the acorn forward, and from where? A computation is not mysterious in the same way; it is a sequence of definite steps, each one following from the last by a fixed rule, with no destination built in from the start, only an unfolding. If life and mind turn out to be the products of computation, then Aristotle's ancient intuition — that the universe has something organism-like about it — would be vindicated, but for reasons Aristotle could never have imagined, and stripped of the purpose he thought was doing the work.

The Trouble with Defining Life: A Family Resemblance, Not a Formula

Before we can ask whether the universe computes life into existence, we need some workable sense of what "life" even picks out — and this turns out to be far harder than it first appears. We recognize life instantly: a bacterium, a redwood, a hummingbird. But try to write down a rule that separates the living from the non-living, applying to all and only living things, and the rule collapses under its own weight.

Consider the usual candidates. Reproduction — but a mule cannot reproduce, and a virus cannot reproduce without hijacking a host cell's machinery, yet nobody doubts a mule is alive or that viral disease is a biological phenomenon. Response to external stimuli — but a thermostat responds to temperature, and a sunflower's phototropism is barely more sophisticated than a simple feedback loop; the criterion is either too narrow or too permissive depending on how strictly you apply it. Growth — but so does a crystal in a supersaturated solution, adding to itself along the lines of its existing lattice, with no metabolism, no information storage, nothing we'd want to call life. Metabolism, the processing of energy to maintain structure — but a candle flame consumes fuel, releases waste heat, and maintains a stable, self-sustaining shape for as long as fuel is available; it looks, in a crude sense, like it's "alive" by this test alone.

What's happening here is not that we've failed to find the right single criterion yet. It's that life is what philosophers call a cluster concept or family resemblance category: something identified not by one necessary-and-sufficient property but by an overlapping bundle of properties, no single one of which is required, and no fixed number of which is sufficient. Real organisms cluster tightly around several of these properties at once — reproduction and metabolism and response to stimuli and internal regulation and evolution by selection — while borderline cases like viruses, prions, or self-replicating RNA molecules in a test tube satisfy only some of them, which is exactly why they sit at the edges of our intuitions and provoke argument rather than settled agreement. This is not a failure of biology; it is a clue. It suggests that "life" is not a natural kind with sharp edges, like "gold" or "electron," but a graded phenomenon — which in turn suggests that instead of asking is this thing alive or not, the more productive question might be how much, and in what way, is this thing organized like the things we call alive. That reframing — from a yes/no category to a matter of degree and kind of organization — turns out to be the thread that connects everything that follows.

Two Origin Stories, and What Turns on the Difference

This uncertainty about what life is feeds directly into a much bigger disagreement about how life began, and the disagreement is not merely academic — it changes what we should expect to find when we look at the rest of the universe.

The first view treats the emergence of the first living organism as a near-miracle: an astronomically improbable convergence of chemical accidents, so unlikely that it plausibly happened exactly once, on this one planet, and would be vanishingly unlikely to repeat itself anywhere else. On this view, Earth's biosphere is less like a common outcome of chemistry and more like a lottery ticket that happened to pay out — and if you ran the tape of the early solar system again, with slightly different initial conditions, you might easily get a sterile planet.

The second view denies that there is any sharp threshold to cross in the first place. On this account, there is no bright line between non-living chemistry and living chemistry — only a long, continuous ramp of increasing organization, starting with simple molecules, moving through self-catalyzing chemical cycles, then through molecules capable of storing and copying information, and eventually arriving at something we're willing to call "alive," without any single step along the way being especially miraculous. The origin of life, on this account, is not an exception to the ordinary processes of physics and chemistry; it is simply one more phase transition, comparable in kind (if not in complexity) to water freezing into ice or a supersaturated solution suddenly crystallizing.

The stakes of this disagreement become obvious the moment you think about the search for life elsewhere. If the first view is right, then the Drake Equation's optimistic estimates of civilizations across the galaxy collapse toward a single, lonely data point — us — and the universe's silence (the "Fermi paradox") stops being surprising and becomes almost expected. If the second view is right, then wherever you find the right raw ingredients — carbon chemistry, liquid water or an equivalent solvent, an energy gradient to exploit — you should expect something organizing itself in life-like ways, given enough time. The two views make different predictions, at least in principle, which is what keeps this from being pure philosophy: it's a live empirical question, one that missions to Europa's ice-covered ocean or Enceladus's plumes are, in a small way, designed to help answer.

From Soup to Cell: What Miller-Urey Actually Showed, and Where It Falls Short

The experimental result that gave the second view — life as a common, near-inevitable outcome — real scientific teeth was Stanley Miller and Harold Urey's classic experiment: sparking electricity through a flask of gases meant to mimic the early Earth's atmosphere, and finding that amino acids, the building blocks of proteins, appeared within days, unbidden, from nothing more exotic than ordinary chemistry and an energy source. Amino acids are not alive. They are not even close to alive — a modern protein might be a chain of hundreds of them, folded into a precise three-dimensional shape that determines its function, and no experiment has ever shown that shape emerging spontaneously in one step. But the ease with which the raw ingredients appeared was itself the striking result. It suggested that the universe's basic chemical vocabulary — the letters life is written in — is not rare or fragile. It falls out of ordinary reactive chemistry almost as a matter of course.

Life, once you have those letters, runs on two chemical families working in a division of labor. Nucleic acids — DNA and RNA — store and transmit the instructions for building an organism: a kind of durable, copyable archive, analogous to a program's source code. Proteins do the actual work described by that archive, serving two roles at once: structural, forming the physical scaffolding and machinery of the cell, and catalytic, speeding up chemical reactions by factors of millions or more, without which the cell's chemistry would be far too slow to sustain anything resembling life. This division — an archive that stores instructions, and a workforce that executes them — is worth sitting with, because it is already, at the level of raw biochemistry, a computational architecture: information storage separated from information execution, exactly the separation that a Turing machine's tape (storage) and read/write head (execution) formalizes in pure logic. Life did not need to wait for engineers to invent this architecture. Chemistry seems to have stumbled into something functionally equivalent to it on its own.

What we still don't understand well is the jump from isolated amino acids to functioning proteins, and, even more so, the origin of the nucleic acids that store the instructions in the first place — a puzzle serious enough that it has its own name, the "chicken-and-egg problem" of the origin of life: proteins are needed to build nucleic acids, but nucleic acids are needed to specify proteins, so which came first? One influential resolution, the "RNA world" hypothesis, proposes that RNA — which, unlike DNA, can both store information and catalyze reactions on its own — briefly played both roles simultaneously, acting as its own archive and its own workforce, before a division of labor eventually split those jobs between DNA and protein. Whether or not this particular hypothesis is correct in its details, the reasoning behind it illustrates the wider point: the origin of life increasingly looks like a search for a plausible sequence of small, individually unsurprising steps, rather than a single impossible leap — which tips the argument, even if only provisionally, toward the second of the two origin stories above. Life, on the evidence so far, appears to be a rather common feature of any universe built from the same physics and chemistry as ours.

There is a deeper physical principle lurking underneath all of this, one the original discussion only gestures at: life is not a violation of the tendency of closed systems to run down into disorder (the second law of thermodynamics), but neither is it a simple exception to it. Living systems are what the chemist and physicist Ilya Prigogine called dissipative structures — organized patterns that persist and even increase their internal order specifically because they are constantly importing energy from their environment and exporting entropy (disorder) back out into it, the way a whirlpool maintains its intricate, stable shape only by continuously channeling water through itself. A living cell, in this light, is not fighting the laws of thermodynamics; it is a particularly elaborate way of obeying them, buying local order by exporting a larger quantity of disorder elsewhere. This gives us a physical, non-mystical answer to a question that otherwise sounds almost paradoxical: how can complexity increase in a universe that is, overall, running down? The answer is that it can increase locally and temporarily, wherever there is an energy gradient to exploit — a sunbeam hitting a leaf, a chemical gradient at a hydrothermal vent — provided the larger system as a whole still pays the entropy bill.

Von Neumann's Universal Constructor: Life as Pure Logic

If biochemistry alone can't tell us what life fundamentally is — since, as we've seen, dissipative structures and self-organizing chemistry are necessary but not obviously sufficient — perhaps a more abstract, substrate-independent description can succeed where chemistry leaves off. This was John von Neumann's ambition: to strip away the wet chemistry entirely and find the logical skeleton underneath, the pattern that makes something alive regardless of what material happens to implement it.

Von Neumann's key insight, worked out in the 1940s in the abstract setting of what we'd now call a cellular automaton (a grid of cells, each following simple local rules based on its neighbors' states), was that a machine capable of exact self-reproduction requires three distinct components working together, and that all three are logically necessary, not optional design choices. First, a description of the machine — a complete, storable blueprint of its own structure, analogous to a genome. Second, a constructor — a mechanism that reads that description and builds a new copy of the machine from raw material, analogous to the cellular machinery (ribosomes and associated apparatus) that reads genetic instructions and assembles proteins. Third, and this is the subtle part, a copier — a mechanism that also duplicates the description itself, unread and unchanged, and hands that duplicate to the offspring, so the new machine has its own blueprint to reproduce with in turn, rather than being built once and then unable to reproduce further.

This three-part architecture is not an accident of von Neumann's design; it is a logical requirement, and it is worth pausing on how strange it is. A machine that could only build a copy of itself, without also copying its own blueprint, would produce sterile offspring — perfect copies structurally, but incapable of building a third generation, because they'd have no description of themselves to pass on. Von Neumann worked this out purely through mathematical logic, years before Watson and Crick determined the physical structure of DNA. When the double helix was finally decoded, biology turned out to have independently implemented almost exactly this architecture: DNA plays the role of the stored description, ribosomes and associated enzymes play the role of the constructor, and DNA replication (copying the archive itself, separately from building proteins) plays the role of the copier. Von Neumann had, in effect, derived the logical necessity of something like DNA replication from pure reasoning about self-reproducing automata, before anyone knew what DNA even was. This is a remarkable convergence, and it is exactly the kind of evidence that gives weight to the idea that life's essential nature is not really about carbon and nitrogen at all — it is about a particular logical architecture, one that happens, in our universe, to have been implemented in biochemistry, but that could in principle be implemented in silicon, in a cellular automaton, or in any sufficiently expressive computational substrate.

Organization as the Mark of Life: The Whole Versus the Sum of Its Parts

Von Neumann's architecture tells us how self-reproduction is logically possible, but it doesn't yet tell us how to measure the difference between a living system and a merely complicated one. For that, we can turn to ideas from algorithmic information theory, the branch of mathematics (developed largely by Andrei Kolmogorov, Ray Solomonoff, and Gregory Chaitin) that measures the complexity of an object not by how big or intricate it looks, but by the length of the shortest possible computer program that could produce it. A string of a million zeros is enormously long but has almost no complexity in this sense, because a tiny program ("print 0, one million times") reproduces it exactly. A string of a million truly random digits, by contrast, has close to maximal complexity in this sense, because no program shorter than the string itself can reproduce it — you simply have to spell it out.

This framework lets us give a sharper version of Chaitin's proposal about what separates living organization from mere aggregation: a living system is one where the complexity of the whole is substantially less than the sum of the complexities of its parts considered separately. This sounds paradoxical until you unpack it. Consider a heap of a trillion independent, unconnected atoms, each jiggling on its own trajectory: to specify the state of the whole heap, you basically have to specify each atom's state individually, because knowing one atom's position tells you almost nothing about any other atom's position. The complexity of the whole is close to the sum of the complexities of the parts — there is no shortcut, no compression available, because there is no relationship between the parts to exploit. Now consider a living cell, where the trillion atoms are bound into interlocking, mutually constraining structures — membranes, enzymes, genetic machinery, feedback loops — such that knowing the state of one part tells you an enormous amount about the state of many other parts, because they are functionally coupled. Here, a vastly shorter description suffices: instead of listing every atom's position, you can largely get away with saying "this is a functioning liver cell in phase G1 of its cycle," and a huge amount of detailed structure follows automatically from that compact description, because the parts are not independent — they are interdependent, mutually determining, effectively "aware" of each other's states through chemical signaling and physical binding. This is what Chaitin meant, in more precise language, by saying life means unity, and that dead matter is best captured as the sum of its parts while living matter is something less than that sum — not less in importance, but less in the number of independent bits of information actually needed to describe it, because the parts have partially collapsed into a single, tightly coupled whole.

Logical Depth: Why Some Complexity Is Meaningful and Some Is Just Noise

Algorithmic complexity alone, however, has an embarrassing blind spot: by this measure, a string of purely random digits is more complex than the human genome, because a random string is, by definition, incompressible — there is no shorter program that generates it — while the genome, despite encoding a staggeringly intricate organism, is compressible in principle (it is, after all, built from a small alphabet of four bases, repeated and rearranged according to evolutionary and biochemical constraints). This means raw algorithmic complexity, taken alone, cannot be what makes an organism special, since blind noise would score higher. Something else is needed to distinguish a genome — meaningful, structured, "deep" complexity — from a string of coin flips — meaningless, unstructured, "shallow" complexity, even in cases where the two might have comparable raw information content.

This is precisely the gap Charles Bennett's notion of logical depth was designed to close, and it deserves a fuller explanation than a quick summary allows. Bennett's insight was to stop asking "how much information does this object contain" and start asking "how much computational work would it take to produce this object from a short, simple starting description." A string of random coin flips has high information content (you can't compress it) but is logically shallow, because the "program" that produces it is essentially the string itself, with almost no computation involved — you just flip the coins and write down the results, with no meaningful process transforming a compact starting point into an elaborate output. Contrast this with the digits of pi: any given long stretch of them looks statistically indistinguishable from random noise, yet they are logically deep, because a very short, simple program (a formula for computing pi) can generate arbitrarily many digits, but only by doing a large and irreducible amount of computational work — you cannot shortcut the calculation, and the eventual output faithfully preserves, in compressed form, all of that computational history.

A living organism, on this view, is logically deep in an even richer sense than the digits of pi, because its "short program" is not a static mathematical formula but an unfolding process: billions of years of evolutionary search, in which countless variations were generated, tested against a punishing environment, and the vast majority discarded, with only the rare improvements retained and built upon by the next round. A genome is, in effect, an extremely compressed record of that entire process — a message whose "buried redundancy," in Bennett's phrase, is recoverable only by an observer willing to do a comparable amount of work to unpack it, whether that means running natural selection forward again in simulation or painstakingly reconstructing evolutionary history from fossils and comparative genomics. This is why an organism feels qualitatively different from a snowflake or a sand dune, even though both display intricate, non-repeating structure: the snowflake's pattern, however elaborate it looks, is the product of comparatively simple, fast physical rules (freezing dynamics) applied over a short time; the organism's pattern is the product of an immensely long, effortful, cumulative search process, whose "cost" is baked irreversibly into the final structure. Depth, unlike raw complexity, tracks time invested, not just intricacy — and this gives us, finally, something close to a rigorous, substrate-independent answer to the question the essay opened with: life is what you get when a system's structure has enough logical depth that its "buried redundancy" could only plausibly have been produced by a long history of accumulated, selected computation, rather than by a short, cheap process or by pure chance.

Is the Universe a Computer? The Digital Physics Program

Once organization, unity, and depth are on the table as the real markers of life, a far larger question becomes almost impossible to avoid: is the universe itself organized this way — is it, at bottom, a computation, with life and mind as unusually deep patterns arising within it?

Several serious physicists have answered yes, in registers ranging from cautious metaphor to full commitment. John Wheeler's contribution was more a research program than a single claim, distilled into his slogan "it from bit": the proposal that every physical "it" — every particle, every field, every force — is not merely described by information but is, at the deepest level, constituted by it; that asking a yes/no question of nature (does the particle go left or right? is the spin up or down?) is not just how we learn about physical reality, but is in some sense how physical reality gets made, moment to moment, from an underlying substrate of information. Ed Fredkin and Tom Toffoli pushed this into an explicitly computational picture, treating the universe as a literal, vast cellular automaton — not metaphorically, but as a genuine claim about physical mechanism, in which particles are patterns propagating through a discrete computational substrate according to fixed local rules, the same way a glider moves through Conway's Game of Life. On this view, physicists are not so much discovering laws of nature in the traditional sense as reverse-engineering an already-running computation that was set in motion long before any of us existed, hitching a ride on someone else's ongoing calculation and trying to figure out which parts of it happen to intersect with what we care about.

Frank Tipler took the most radical position of the group, treating the physical universe as strictly equivalent to its own simulation when viewed at a sufficiently abstract level — not merely simulable in principle, but identical, in every respect that matters, to an abstract computational process. This is a stronger claim than Wheeler's or Fredkin's, because it collapses the distinction between "the universe" and "a description of the universe running as a program" altogether, rather than merely proposing information as the fundamental ingredient of physics.

It's worth noting that this whole family of ideas has a more precise modern descendant in what's sometimes called the Church-Turing-Deutsch principle: the proposal, associated with David Deutsch's work on quantum computation, that every finite physical system can in principle be simulated to arbitrary accuracy by a universal computing device. If true, this principle would mean that computation is not just one useful model for physics, but is built into the very structure of what physical law permits — that "being simulable" is a property built into the fabric of any universe governed by consistent, finite laws, our own included. This gives the older, more poetic versions of the "universe as computer" idea (Wheeler's slogan, Fredkin's cellular automaton) a more rigorous modern anchor, even for those who remain skeptical of the strongest, most literal versions of the claim.

The Continuum Objection, and the Case for a Discrete Universe

The most serious scientific objection to this whole picture came from an unlikely source: Richard Feynman, one of the founders of the very field — quantum computation — that would later make digital physics fashionable again. Feynman's worry, when he considered whether nature could ever be exactly simulated by a finite computation, was structural rather than merely practical: our best theories of physics treat space and time as genuinely continuous, infinitely subdivisible, with no smallest possible distance or duration — and a computation, by its nature, proceeds through a finite number of discrete steps. If space and time really are continuous all the way down, with no floor, then an exact, finite simulation of even a small region of space for a small duration of time would require, in the limit, an infinite number of computational steps — which is not merely impractical but is a difference in kind, not degree, between computation and physical reality. This is a serious objection, not a hand-wave, and it deserves to be taken as seriously as Feynman intended it.

But, as Paul Davies has pointed out, the apparent continuity of space and time is not something we've ever actually verified — it is a working hypothesis, baked into the mathematics of our theories because continuous mathematics (calculus) happens to be enormously convenient and has worked extraordinarily well at every scale we've so far been able to probe, not because anyone has confirmed there is no smallest possible "grain" to reality. Our best current experiments and observations constrain the graininess of time to be smaller than roughly 10⁻²⁶ seconds — an extraordinarily short interval, but not zero. Davies' analogy is apt: a movie film advancing one frame at a time looks perfectly smooth and continuous to an eye that cannot resolve the individual frames, and the fact that we haven't yet detected the "frame rate" of reality does not mean reality has no frame rate; it may simply mean our instruments aren't yet fine enough to see the individual frames.

This is not idle speculation dressed up in physics language — it connects directly to some of the most active research programs in fundamental physics. Many approaches to quantum gravity (the unfinished project of reconciling general relativity's smooth spacetime with quantum mechanics's granular, probabilistic rules) independently arrive at some notion of a smallest meaningful length, the Planck length (roughly 10⁻³⁵ meters), below which the very concepts of "distance" and "duration" may cease to have their ordinary meaning, dissolving into something more like discrete, combinatorial structure — spin networks, causal sets, or other candidate discrete substrates, depending on which research program you consult. Separately, the holographic principle, motivated by results in black hole thermodynamics, suggests that the maximum amount of information that can be packed into any region of space is proportional not to its volume but to the area of its boundary, measured in fundamental, discrete units — a deeply strange result that only makes sense if information, at the most basic level, comes in indivisible chunks rather than a smooth continuum. None of this proves the universe is a computer in Fredkin's literal sense. But it does mean Feynman's continuum objection, while entirely reasonable given the physics available at the time, may rest on an assumption — true continuity — that independent lines of cutting-edge research are now actively questioning from a completely different direction, for reasons that have nothing to do with the philosophy of simulation at all.

Can a Simulation Be Conscious? Tipler, Penrose, and the Limits of Verification

If the universe can, in principle, be described as computation, a sharper and more unsettling question follows immediately: could the conscious beings inside that computation — could we — be simulated rather than "fundamentally real," in whatever sense that phrase is even supposed to mean, and would there be any way to tell the difference?

Tipler's argument here is a piece of careful, if unsettling, logic, and it's worth reconstructing it step by step rather than just stating the conclusion. Take any test a person might use to convince themselves that they genuinely exist and are not merely simulated: noticing that they are thinking, interacting with an external world that pushes back in consistent ways, remembering a continuous personal history, reflecting on the very fact that they are reflecting. Now notice that a sufficiently detailed simulation of a person would, by the very completeness of the simulation, perform every one of these same tests and get every one of the same results — because the simulated person's thoughts, memories, and reflections are themselves part of what's being simulated, indistinguishable from the inside from the "real" article. The crucial move is realizing that this isn't a limitation of some particular clumsy simulation technology that better engineering could eventually fix; it's a structural, in-principle barrier. A simulated observer's only tools for investigating their own reality are tools that exist within the simulation, which means those tools can never, even in principle, reach outside the simulation to check whether there's anything "underneath" it — the way a character in a novel has no access to the paper and ink, or the author, that constitute the "reality" underlying their fictional world, no matter how vividly the character might reason about their own existence.

Tipler's conclusion is a specific philosophical move: since no experiment, real or imaginable, could ever distinguish a "fundamentally real" physical universe from a sufficiently complete and self-consistent computational one, the distinction between them carries no empirical content, and — adopting a broadly empiricist stance that treats unverifiable distinctions as meaningless rather than merely unknown — should be set aside as a Kantian "thing-in-itself": a concept we are logically forced to gesture at but can never actually cash out in observation, and therefore not a fact about the world so much as an artifact of how we've phrased the question. On this view, the sensible conclusion isn't "we can't know whether the universe is real or simulated" but rather "the question, as posed, doesn't actually distinguish two different possible states of affairs" — rather like asking whether the number seven is "really" red.

Roger Penrose represents the most serious and specific dissent from this entire line of reasoning, and it is worth being precise about where exactly he disagrees, because it is not where casual summaries usually place him. Penrose does not simply doubt that current computers can replicate consciousness — a comparatively mild and widely shared skepticism. His claim is much stronger: that the physical processes which give rise to conscious awareness are not, even in principle, the kind of process that any computation — however powerful, however complete — could faithfully reproduce, because (in Penrose's specific and controversial argument, developed with the anesthesiologist Stuart Hameroff) consciousness may depend on physical processes, possibly involving quantum effects in the brain's microstructure, that are fundamentally non-computable in the technical mathematical sense established by Gödel's incompleteness theorems and Turing's halting problem. If Penrose is right — and this remains a minority position among physicists and neuroscientists, sharply contested on both physical and biological grounds — then the entire "universe as computer" picture, however well it might describe rocks, weather, and galaxies, hits an impassable wall exactly at the point that matters most to the question of whether we could be simulated: it may describe everything about a person's physical brain and behavior, while remaining permanently, structurally unable to account for the fact that there is something it is like to be that person — the philosopher's "hard problem" of consciousness, sharpened by Penrose into a specific, falsifiable-in-principle claim about computability rather than left as a vague mystery.

This same underlying puzzle — that a sufficiently good simulation would be indistinguishable from the inside — has since become one of the more widely discussed arguments in contemporary philosophy of mind and cosmology, under the general heading of "simulation arguments," which reason from the sheer number of possible simulated minds a sufficiently advanced civilization could in principle run to a probabilistic conclusion about which kind of world any given observer is more likely to find themselves in. The details of that later literature differ from Tipler's framing, but the core structural insight — that internal, first-person verification cannot in principle distinguish simulated from "base level" reality — is exactly the same one Tipler was pointing at.

Endophysics: Why We Can Never Step Outside to Check

There is a further wrinkle, developed by the physicist Karl Svozil, that doesn't so much resolve the Tipler/Penrose disagreement as explain, at a deeper level, why it is so stubbornly hard to resolve — and this piece of the puzzle deserves more attention than it usually gets, because it reframes the entire debate as being about the structure of observation itself, not just about consciousness or computation.

Svozil distinguishes two fundamentally different postures a scientist can take toward a system under study. In exophysics (from the Greek for "outside"), the observer and the system form a clean, two-level hierarchy: the observer sits outside the system, peers in, and measures whatever they like without disturbing what's being measured — information flows in one direction only, from system to observer, the way an astronomer observes a distant galaxy without the galaxy's behavior depending in any way on the astronomer's presence. Essentially all of laboratory science, and essentially all of our everyday intuitions about "objective observation," are built on this exophysical model, because in practice the disturbance an observer causes is negligible compared to the system being studied.

Endophysics (from the Greek for "inside") describes a completely different situation, one where the observer is not outside the system but is themselves a constituent part of the very system under investigation, built from the same stuff, governed by the same laws, with no external vantage point available even in principle. Here the clean hierarchy collapses: "measuring device" and "thing being measured" are no longer permanently distinct roles but can trade places depending only on which part of the system you're currently treating as the observer, and information flows both ways, contaminating every measurement with the observer's own presence and activity inside the very system being measured. This is not a hypothetical curiosity; it is arguably the actual epistemic situation of every physicist who has ever studied quantum mechanics, where the act of measurement is now well established to unavoidably disturb the system being measured, in a way that cannot be reduced below a certain fundamental limit no matter how careful or clever the experimenter is — the observer effect is not a matter of clumsy instruments, but a structural feature of what it means to measure something from within the same physical universe that contains both the measuring device and the thing measured.

This distinction explains, with real precision, why the question "is our universe fundamentally real or a simulation" is so resistant to closure. We are not exophysical observers with a privileged, external vantage point on the cosmos, the way a programmer sits outside the computer running their program, able in principle to pause it, inspect its internals, and compare the running simulation against the intended design. We are endophysical participants, built entirely from the same physical (or computational) substrate as the universe we are trying to characterize — which means any theory we construct about whether that substrate is "fundamental" or itself simulated is, itself, a product of computation happening inside the very system whose fundamental status is in question. There is a structural echo here of Gödel's incompleteness theorems, which showed that any sufficiently powerful formal system contains true statements about itself that the system cannot prove using only its own internal resources — self-reference, once again, runs into a wall precisely when a system tries to fully characterize itself from within, using only tools the system itself provides. Archimedes once imagined that, given "a point outside the world," he could move the entire Earth with a lever of sufficient length — a boast about mechanical leverage, not metaphysics, but one that has since become an apt metaphor for exactly the kind of external vantage point that endophysics says is permanently unavailable to any observer who is, themselves, part of the world being levered.

Deutsch's Insight: Why the Whole Edifice Rests on a Contingent Fact

It's worth ending on a smaller, more grounded point, made by the physicist David Deutsch, because it quietly ties this entire chain of speculation back to something concrete and, unlike most of what precedes it, genuinely uncontroversial — and it deserves more weight than a passing mention, because it reframes everything before it as resting on a foundation that could, in principle, have been otherwise.

Why can we build calculators? Why can human beings do arithmetic in their heads at all? The question sounds almost too simple to be worth asking, but Deutsch's answer is genuinely surprising: this capacity is not guaranteed by logic or mathematics in the abstract, the way the truths of arithmetic themselves are supposedly guaranteed. It depends, instead, on a contingent, empirical fact about this particular universe: that the laws of physics happen to permit the construction of physical systems — whether silicon transistors, mechanical gears, or networks of neurons — whose behavior tracks and instantiates abstract operations like addition, subtraction, and multiplication. In a universe with different physical laws, arithmetic would remain just as true in the abstract (two plus two would still equal four as a fact of pure mathematics), but there might be no way to physically compute it — no possible arrangement of matter and energy, in that hypothetical universe's physics, capable of tracking the operation reliably. Addition, multiplication, and the rest would remain non-computable functions: things we might still reason about abstractly, invoke as steps in what would then have to be called "non-constructive" proofs, but never actually perform, because no physical process in that universe's laws would be capable of tracking them.

That single observation reframes everything that came before it in this essay. The question of whether life is common, whether organisms are logically deep in Bennett's sense, whether the cosmos itself is a cellular automaton, whether consciousness could ever be simulated, whether an endophysical observer could ever step outside their own universe to check — all of these turn out to be, at bottom, questions about what a particular, contingent set of physical laws happens to make computable and organizable. Life is what these specific laws allow chemistry to build, given enough time and the right gradients. Minds are what these specific laws allow neurons (or perhaps, if Penrose is wrong, silicon) to compute. And our very capacity to ask any of these questions — to reason, to calculate, to wonder whether we ourselves are simulated — is itself made possible only because physics, in this universe, happens to permit exactly the kind of physical processes that can track logical and arithmetical operations. We are not external auditors examining the source code of reality from a safe distance outside it. We are, in the fullest and most literal sense available to us, running on it.

Living With an Unanswerable Question

What makes this whole cluster of ideas so durable — stretching from Aristotle's teleological cosmos through Miller and Urey's flask of sparking gases to von Neumann's self-reproducing automata, Chaitin's and Bennett's measures of depth and organization, and finally to Tipler's and Svozil's arguments about the limits of self-knowledge from within a system — is not that any of it settles the question of what life is or whether the universe computes. None of it does, and arguably none of it can, for the endophysical reasons Svozil's argument makes precise: we are asking these questions from inside the very system we're trying to characterize, using cognitive and computational resources that are themselves part of what's under investigation, with no lever long enough and no point outside the world to stand on while we pull it.

What this body of ideas offers instead is something more valuable than a final answer: a genuinely better set of questions, sharpened by a century of mathematics and physics that Aristotle didn't have available. Instead of asking whether the universe has a purpose, we can ask whether it has a computational structure, and what kind. Instead of asking whether something is alive in a binary sense, we can ask how organized, how integrated, how logically deep its structure is, and by how much the whole outruns the sum of its parts. Instead of asking whether we can prove we're not simulated, we can ask what, precisely, a first-person observer embedded inside a system could ever hope to determine about that system's ultimate nature — and recognize that the honest answer, "less than we'd like, and perhaps nothing at all," is itself a substantive discovery about the structure of knowledge, not a failure to find one. That may be the deepest insight buried in all of this: not a solution to the riddle of life and the universe, but a rigorous, hard-won understanding of exactly why the riddle resists solving from where we necessarily stand to ask it.

Summary

The quest to identify the origins of life on Earth has long been a subject of scientific debate, with theories ranging from Charles Darwin’s "warm little pond" to hydrothermal vents and cosmic impacts. A new study led by Professor Richard Zare at Stanford University introduces a compelling new candidate for the spark of life: "microlightning" generated within the fine mist of crashing waves and waterfalls. This research suggests that the physical action of water spray could have provided the necessary energy to transform simple inorganic gases into the complex organic molecules required for biology.

The Mechanism of Microlightning

Unlike the massive atmospheric lightning bolts explored in the famous Miller-Urey experiments of the 1950s, microlightning occurs at a microscopic scale. Scientists discovered that microdroplets in water sprays carry opposing electrical charges. When these droplets collide or come into close proximity, tiny sparks leap between them. While these discharges travel only a few billionths of a meter, they possess sufficient energy to act as a catalyst for chemical transformations. This process occurs constantly in environments where water is agitated, such as coastal surf or rocky waterfalls, offering a more frequent and localized energy source than rare atmospheric lightning strikes.

Prebiotic Synthesis and Experimental Results

In laboratory simulations, Zare’s team sprayed water into a mixture of gases representative of Earth’s early atmosphere, including nitrogen, methane, carbon dioxide, and ammonia. The resulting microlightning triggered rapid chemical reactions that produced several foundational building blocks of life:

• Hydrogen Cyanide: A volatile but essential precursor for organic synthesis.

• Glycine: A fundamental amino acid used in the production of proteins.

• Uracil: One of the four nucleobases in RNA, critical for genetic information and cellular function.

Scientific Context and Implications

The discovery addresses a significant critique of previous lightning-based theories—specifically, that large-scale lightning is too infrequent and its products too dispersed to facilitate the concentrated chemistry needed for life. By contrast, microlightning occurs in "crevices in rocks" and coastal areas where chemicals can naturally accumulate and react over time. Experts in the field, such as Dr. Eva Stueeken and Prof. David Deamer, suggest that while further research is needed to quantify the global impact of this mechanism on the early Earth, it represents a significant new entry in the list of energy sources that could have driven prebiotic organic synthesis. This "primordial surf" hypothesis provides a bridge between non-living chemistry and the emergence of the first biological systems.

Transcript

Primordial surf: ‘microlightning’ in mist may have sparked life on Earth, study finds

Tiny lightning streaks in fine spray can power chemical reactions that generate molecules for life, scientists say.

Charles Darwin thought it started in a warm pond. Others point to comets that ploughed into Earth. And some suspect a bolt from the blue, a lightning strike into the ocean. How life started on Earth may forever be a mystery, but new research proposes a radical idea: that crashing waves and waterfalls may have kicked off the process by throwing up mists of water.

In experiments at Stanford University, chemists discovered that microdroplets in fine sprays of water generate streaks of “microlightning”. When surrounded by the right mix of gases, these sparks power chemical reactions that synthesise many molecules for life.

Prof Richard Zare, a chemist who led the team, said: “This is a real contribution to understanding how you can go from non-life to life. You have water sprays all over the place, particularly around rocks, and there are crevices in rocks where these chemicals can accumulate.”

There is no consensus about the origins of life, and no shortage of hypotheses. When Darwin published On the Origin of Species in 1859 he described how evolution generated the diversity of life, but not how it started. He speculated, however, that chemicals could have interacted in “a warm little pond” from which living cells eventually emerged.

Hot undersea vents that spew mineral-rich fluids are now considered to be leading contenders for fostering life. Impacting comets may have helped, too, by creating shock waves that converted simple organics into amino acids, the constituents of proteins.

Lightning strikes might also have lent a hand. The idea that lightning created the ingredients for life gained traction in 1953 when Stanley Miller and Harold Urey at the University of Chicago reported that electrical discharges in a simulated early Earth atmosphere produced amino acids. But the hypothesis has its critics: lightning is too infrequent, they say, and the chemicals produced simply drift away.

Zare’s team took to a dark room to investigate the electrical properties of water sprays. They found that droplets carry opposing charges and when they come together, tiny sparks leap between them. Unlike lightning bolts that cover miles, microlightning travels a few billionths of a metre.

While the effect is faint, it carries enough energy to drive chemical reactions. Writing in Science Advances, the researchers describe how they sprayed water into a mixture of nitrogen, methane, carbon dioxide and ammonia. This led to the rapid formation of key molecules including hydrogen cyanide; glycine, an amino acid involved in protein production; and uracil, a building block of RNA found in all living cells. “We propose that this is a new mechanism for the prebiotic synthesis of molecules that constitute the building blocks of life,” Zare said.

Dr Eva Stueeken, who studies the origins of life at the University of St Andrews, said the work was fascinating. “It opens up an array of possibilities that we need to explore further, using different gas and fluid compositions,” she said. “It will also be important to quantify how significant this mechanism would have been on a global scale for the generation of prebiotic molecules.”

Prof David Deamer at the University of California, Santa Cruz, who has worked with Zare but not on the latest study, said microlightning “can now be added to the list of possible energy sources available to drive organic synthesis before life began.”

Summary

The Enigma of Molecular Homochirality

One of the most profound mysteries in biology is "homochirality"—the fact that life uses only one of two possible mirror-image forms of certain molecules. While synthetic chemical processes typically produce equal amounts of "left-handed" and "right-handed" enantiomers, living cells are strictly asymmetrical. For instance, the sugars in DNA are exclusively right-handed, while the amino acids in proteins are left-handed. This biological preference was first glimpsed by Louis Pasteur in 1848, but the mechanism that "broke the mirror" during the origins of life has remained elusive for over 170 years.

The Chiral-Induced Spin Selectivity (CISS) Effect

Recent research suggests that magnetism may be the missing link between geophysics and biochemistry. The foundation of this theory is the Chiral-Induced Spin Selectivity (CISS) effect, discovered by Ron Naaman. This phenomenon dictates that chiral molecules act as electron filters based on quantum spin. Electrons with a specific spin orientation move more efficiently through one enantiomer than the other. Consequently, when chiral molecules approach a magnetic surface, they are either attracted or repelled based on whether their spin alignment matches the surface’s magnetic orientation.

Experimental Breakthroughs at Harvard

A team led by Dimitar Sasselov and S. Furkan Ozturk at Harvard University applied the CISS effect to prebiotic chemistry. They focused on ribo-aminooxazoline (RAO), a precursor to RNA that crystallizes easily. In their experiments, the researchers placed RAO solutions on magnetized surfaces. They discovered that the magnetic orientation of the surface dictated the handedness of the resulting crystals with 100% efficiency. While the initial experiments used strong magnets, follow-up research demonstrated that chiral molecules adsorbed onto magnetic surfaces can create local magnetic fields strong enough to sustain this bias without an external power source, suggesting that Earth’s natural magnetic field could have served as the original "chiral agent."

Propagating Homochirality through Networks

The significance of this discovery lies in its ability to explain how a single biased event could cascade into a global biological standard. The researchers propose that if a common RNA precursor like RAO became homochiral via magnetic minerals in primordial lakes, that bias would propagate. Evidence suggests that right-handed RNA analogs link to left-handed amino acids significantly faster than to right-handed ones, providing a direct pathway from chiral RNA to the left-handed proteins seen in nature today. This suggests that the entire network of life's chemistry could be traced back to the magnetic properties of the early Earth.

Scientific Reception and Future Verification

The hypothesis has been praised for its geological relevance and experimental rigor, though it faces healthy skepticism. Critics note that the full polymerization of RNA in prebiotic conditions remains to be proven and that geological evidence from ancient sites, such as the Pilbara in Australia, is needed to confirm the theory outside of a laboratory setting. Despite these hurdles, the research offers a compelling, physics-based solution to a problem that has historically relied on "fluke" theories, potentially closing one of the oldest gaps in our understanding of life's origins.

Transcript

Magnetism May Have Given Life Its Molecular Asymmetry

By Yasemin Saplakoglu

September 6, 2023

The preferred “handedness” of biomolecules could have emerged from biased interactions between electrons and magnetic surfaces, new research suggests. Living things are asymmetrical, even at the molecular level: Although many essential biomolecules exist in distinct mirror-image forms, cells tend to use just one of those forms exclusively.

Introduction

In 1848, when Louis Pasteur was a young chemist still years away from discovering how to sterilize milk, he discovered something peculiar about crystals that accidentally formed when an industrial chemist boiled wine for too long. Half of the crystals were recognizably tartaric acid, an industrially useful salt that grew naturally on the walls of wine barrels. The other crystals had exactly the same shape and symmetry, but one face was oriented in the opposite direction.

The difference was so stark that Pasteur could separate the crystals under a magnifying lens with tweezers. “They are in relation to each other what an image is, in a mirror, in relation to the real thing,” he wrote in a paper that year.

Though Pasteur didn’t know it, in the crystallized dregs of that wine, he had stumbled across one of the deepest mysteries about the origins of life on Earth. What he was seeing was a mixture of tartaric acid molecules that had identical atomic compositions and mirror-image arrangements of those atoms in space. They had the property later called “chirality” after the Greek word for “hand”: Just as our left and right hands are symmetrical opposites of each other, the left- and right-handed versions (or enantiomers) of the tartaric acid molecules are distinct and nonequivalent.

The significance of Pasteur’s observation went beyond the discovery of chirality — there was also the remarkable reason he was seeing it. The synthetic crystals were a mixture of the tartaric acid enantiomers because the boiling process allowed left- and right-handed versions to form in equal numbers. But in the natural crystals from wine barrels, all the tartaric acid molecules were right-handed — because the grapes used for the wine, picked from living vines, only made that enantiomer.

Chirality is a signature of life as we know it. Over and over, biochemists have found that when living cells use chiral molecules, they use one chirality exclusively. The sugars that make up DNA, for example, are all right-handed. The amino acids that make up proteins are all left-handed. If the wrong enantiomers slip into pharmaceuticals, the effects can sometimes be toxic or even lethal.

Some event or series of events early in the history of life must have “broken the mirror,” as biochemists put it, throwing life into molecular asymmetry. Scientists have debated why life became homochiral, and whether it needed to happen or if it was purely a fluke. Were chiral preferences impressed on early life by biased samples of molecules arriving from space, or did they somehow evolve out of mixtures that started out as equal parts right- and left-handed?

“Scientists have been mystified by this observation,” said Soumitra Athavale, an assistant professor of organic chemistry at the University of California, Los Angeles. “They’ve come up with all sorts of proposals over the years, but it’s difficult to come up with proposals which are actually relevant geologically.” Moreover, while many theories could explain why one type of molecule might have become homochiral, none of them explained why whole networks of biomolecules did.

Recently, a group at Harvard University published a series of papers that present an intriguing solution for how life’s homochirality emerged. They suggest that magnetic surfaces on minerals in bodies of water on the primordial Earth, charged by the planet’s magnetic field, could have served as “chiral agents” that attracted some forms of molecules more than others, kicking off a process that amplified the chirality of biological molecules, from RNA precursors all the way to proteins and beyond. Their proposed mechanism would explain how a bias in the makeup of certain molecules could have cascaded outward to create a vast network of chiral chemistry supporting life.

It’s not the only plausible hypothesis, but “it’s one of the coolest because it ties geophysics to geochemistry, to prebiotic chemistry, [and] ultimately to biochemistry,” said Gerald Joyce, a biochemist and president of the Salk Institute who was not involved in the study. He is also impressed that the hypothesis is backed by “actual experiments” and that “they’re doing this under realistic conditions.”

The CISS Effect

The roots of the new theory about homochirality reach back almost a quarter century to when Ron Naaman, a professor of chemical physics at the Weizmann Institute of Science in Israel, and his team discovered a critical effect of chiral molecules. Their work focused on the fact that electrons have two key properties: They carry a negative charge, and they have “spin,” a quantum property analogous to intrinsic clockwise or counterclockwise rotation. When molecules interact with other molecules or surfaces, their electrons can redistribute themselves, polarizing the molecules by creating a negative charge at their destination and a positive charge at their starting point.

Naaman and his team discovered that chiral molecules filter electrons based on the direction of their spin. Electrons with one spin orientation will move more efficiently across a chiral molecule in one direction than the other. Electrons with the opposite spin move more freely the other way.

To understand why, imagine throwing a Frisbee that glances off the wall of a hallway. If the Frisbee hits the right-hand wall, it will bounce forward only if it’s rotating clockwise; otherwise, it will bounce backward. The opposite will happen if you hit the Frisbee off the left-hand wall. Similarly, chiral molecules “scatter the electrons according to their direction of rotation,” Naaman said. He and his team named this phenomenon the chiral-induced spin selectivity (CISS) effect.

Because of that scattering, electrons with a given spin end up aggregating at one pole of a chiral molecule (and the right-handed and left-handed versions of the molecule gather opposite spins at their respective poles). But that redistribution of spins affects how the chiral molecules interact with magnetic surfaces because electrons spinning in opposite directions attract one another, and those spinning in the same direction repel one another.

Consequently, when a chiral molecule approaches a magnetic surface, it will be drawn closer if the molecule and the surface have opposite spin biases. If their spins match, they will repel each other. (Because other chemical interactions are also going on, the molecule can’t simply flip to realign itself.) So a magnetic surface can act as a chiral agent, preferentially interacting with only one enantiomer of a compound.

In 2011, in collaboration with a team at the University of Münster in Germany, Naaman and his team measured the spin of electrons as they moved through double-stranded DNA, confirming that the CISS effect is both real and strong.

That’s when research into the effect and its possible applications “started to boom,” Naaman said. He and his team, for example, developed several ways to use the CISS effect to remove impurities from biomedicines, or to exclude the wrong enantiomers from drugs to prevent major side effects. They’ve also explored how the CISS effect might help to explain the mechanisms of anesthesia.

But they only began working seriously on the idea that the CISS effect plays a part in the rise of biological homochirality after they were invited to collaborate on a hypothesis by a team at Harvard led by the astronomer Dimitar Sasselov and his graduate student S. Furkan Ozturk.

A Physics Perspective

Ozturk, the young lead author on the recent papers, came across the homochirality problem in 2020 when he was a physics graduate student at Harvard. Unhappy with his research on quantum simulations using ultracold atoms, he flipped through a science magazine detailing 125 of the biggest mysteries in the world and learned about homochirality.

“It looked really like a physics question because it’s about symmetries,” he said. After reaching out to Sasselov, who is the director of Harvard’s Origins of Life Initiative and who was already interested in the question of homochirality, Ozturk switched over to become a student in his lab.

Ozturk and Sasselov soon hit on an idea based on the CISS effect. They imagined a primordial setting like a shallow lake where there were surfaces full of magnetic minerals and the water contained a mixture of chiral precursors to nucleotides. They theorized that ultraviolet light could have ejected many electrons from the magnetic surfaces, and many of those electrons would have had the same spin. The ejected electrons might then have interacted preferentially with specific enantiomers, and the resulting chemical reactions might then have preferentially assembled right-handed RNA precursors.

In April 2022, Ozturk traveled to Naaman’s lab in Israel, thrilled by the prospect of testing their hypothesis. His excitement was short-lived. Over the next month as he worked with Naaman, the idea fell apart. It “did not work,” Ozturk said, and so he returned home, dejected.

But then Ozturk had another idea. What if the CISS effect wasn’t manifesting as a chemical process but as a physical one?

Naaman’s group had shown that they could use magnetic surfaces to crystallize enantiomers preferentially. And crystallization would be the easiest way for purified collections of enantiomers to assemble. Ozturk mentioned that to John Sutherland, their collaborator at the MRC Laboratory of Molecular Biology in the U.K. “And I said, drop everything to do with electrons and just focus on the crystallization,” Sutherland said.

Sutherland was excited by the crystallization aspect because he and his team had already independently discovered that an RNA precursor called ribo-aminooxazoline (RAO) can synthesize two of the four building blocks of RNA. RAO also “crystallizes beautifully,” Sutherland said. Once a crystal seed forms from the enantiomer that is attracted to the surface, the crystal preferentially grows by incorporating more of the same enantiomer.

Ozturk remembers Sutherland telling him that it would be “game over” if the CISS effect idea worked. “Because it was so simple,” Ozturk said. “It was doing it on a molecule that was so central to the origin of life chemistry that if you can manage to make that molecule homochiral, you can make the entire system homochiral.”

Ozturk got to work in the Harvard lab. He put magnetite surfaces onto a petri dish and filled it with a solution containing equal amounts of left-handed and right-handed RAO molecules. He then put the dish on a magnet, put the experiment in the fridge and waited for the first crystals to appear. At first, the team found that 60% of the crystals were single-handed. When they repeated the process, their crystals were 100% of the same chirality.

As they reported in a study published in June in Science Advances, if they magnetized the surface one way, they created crystals that were purely right-handed; if they magnetized it the other way, the crystals were purely left-handed. “I was very surprised, because I’m super familiar with experiments that do not work,” Ozturk said. But this one “worked like a charm.”

Multiply and Amplify

But they still had a major problem: The magnet they used in their experiment was about 6,500 times stronger than Earth’s magnetic field.

So Ozturk returned to the Weizmann Institute last November, and he and Naaman then worked on a follow-up experiment in which they didn’t use an external magnetic field at all. Instead, they found that when the chiral molecules were adsorbed onto the magnetic surfaces, they created a highly local magnetic field over the surface that was up to 50 times as strong as Earth’s magnetic field. Their findings have been accepted by a peer-reviewed journal but not yet published.

“You’re coercing the neighborhood to be magnetized, which makes it even easier for the crystals to keep forming,” Joyce said. That self-perpetuating effect makes the scenario plausible, he added.

Athavale agrees. The fact that you don’t need a highly magnetic field for the CISS effect to occur is “really nice, because now you have seen a possible geological setting,” he said.

But the real key to creating homochirality is to look at how the effect could have been amplified across a network of interacting molecules. “The most important aspect of all this is not that we managed to find yet another way to get a chiral product,” Sasselov said, but that his group had found a route to creating a homochiral network.

In a paper featured on the cover of The Journal of Chemical Physics in August, Ozturk, Sasselov and Sutherland proposed a model for how chiral information might propagate across a prebiotic network. Sutherland and his group had previously shown that analogs of right-handed transfer RNA molecules — which bind amino acids and bring them to the ribosome to make proteins — link to left-handed amino acids 10 times faster than to right-handed ones. The finding suggests that chiral RNA preferentially makes proteins of the opposite chirality, as is seen in nature. As the researchers wrote in the paper: “Therefore, the biological homochirality problem may be reduced to ensuring that a single common RNA precursor (e.g., RAO) can be made homochiral.”

The study didn’t directly explain why life’s preferred nucleotides are right-handed and its amino acids are left-handed, Ozturk said. But these new findings suggest that the determining factor was the magnetization induced by the Earth’s field. Athavale noted that even if the crystallization process happened in 100 primordial lakes, Earth’s magnetic field would ensure that they all produced precursors with the same handedness rather than a mixture.

Joyce noted that there’s a “cool little twist” if the magnetic field gave such a bias: If life started in the northern hemisphere and favored molecules with one handedness, then it would have shown the opposite handedness if it had arisen in the southern hemisphere.

The propagation of chirality between families of molecules is still highly hypothetical, Athavale noted, though it’s good to get people thinking. Sasselov agrees. “The idea of this paper is to motivate people to go and do these experiments,” he said.

Wentao Ma, an origins-of-life researcher at Wuhan University in China, said that the new papers mark “interesting progress.” But he would need to see the CISS effect lead to the polymerization of RNA to see it as a complete answer. “If they can achieve this result, I think we’re not far away from the … solution,” he said.

“I really like the CISS effect,” said Noémie Globus, an astrophysicist who is working on the homochirality problem. What would be more persuasive, she said, would be for the researchers to check whether meteorites containing an excess of amino acids with a particular handedness (which have been found before) also contain excess magnetic particles. She also noted that different theorized mechanisms could all have been creating homochirality in different molecules.

Jeffrey Bada, an emeritus professor at the Scripps Institution of Oceanography at the University of California, San Diego, is skeptical of the idea. He doesn’t believe that RNA could have been synthesized in primordial conditions as the first self-replicating molecule. “No one’s made RNA in a prebiotic context,” he said, because there are too many issues with the stability of the molecule.

Sutherland’s team is still working to show that the other two types of nucleotides can be made from the RNA precursor molecule. “I think we’re pretty damn close,” Sutherland said. “But my group will tell you that I’ve been saying that for 22 years.”

Whether the CISS effect represents the solution, part of the solution or no solution at all, there are obvious next steps to testing it. “It’s got all the aspects of a nice hypothesis where you’re coming up with something creative, something which is feasible, and then something which can ultimately be tested,” Athavale said. The most convincing next step, he thinks, would be to show geological evidence that the process could have happened outside the lab.

Over a Zoom call, Ozturk held up a flat black rock that he had picked up on a trip to Australia, a place filled with magnetic iron rocks on which he’s hoping to replicate his experiments. He also wants to make future tests of the idea more dynamic: The primordial lakes where he thinks the early molecules formed would have had streams and flows of material, as well as natural “wet-dry” cycles driven by rains and high temperatures, that would allow crystals to form and dissolve, form and dissolve.

Though the mystery of homochirality is far from settled, Ozturk has received some enthusiastic encouragement from his mentors for his work on the CISS effect explanation. In April, he gave a talk at Harvard about the Sasselov group’s research, and one of his idols attended. Matthew Meselson, a geneticist and molecular biologist who experimentally confirmed how DNA is replicated, sat in the front row as Ozturk wrote out his findings on a chalkboard. The 93-year-old geneticist told Ozturk afterward that he was so glad he had lived long enough to see this problem being solved. He later gave Ozturk a signed copy of one of his books. “Already you have solved a deep problem,” he wrote in it. “I wish you the best fortune.”