What You Are

Here's something you have never once experienced: anyone else's headache.

You've seen people with headaches. You've heard about headaches in more detail than you wanted. But the ache itself, from the inside? Never. Not your best friend's, not your mother's, not the guy on the bus pressing his thumbs into his temples. You get exactly one inside, and it's yours.

That's so normal that it's hard to notice how strange it is. There's one world out there: the same air, the same sunlight, the same laws of physics for everybody. And somehow it shows up as eight billion separate private screenings, each one sealed inside its own skull.

Think about a concert. One band, one room, one set of sound waves bouncing off the same walls. The physics is identical for everyone in the building. And yet there are ten thousand completely separate experiences of that concert, each with its own view of the stage, its own sore feet and its own opinion about the drummer.

Same band, same air, same physics. Ten thousand insides.

So what is an inside? What are you, that the world shows up this way for you and for nobody else?

This is the first of three posts about a theory with a surprising answer. This one is about what you are. The second is about time: whether the past is really gone, and in what sense you could travel in it. The third asks what happens when a mind lets go of the body.

Here's where this one is headed. In the theory's smallest working model, almost everything falls apart, and the only things that last are a few rhythms. The theory's bet is that you're one of them. The biggest step in that, from the model to a living person, hasn't been shown, and I'll mark it every time I rely on it.

A word on what you're reading. Recognition Science is the framework my institute works on, and Recognition Boundary Theory is the part of it that asks where points of view come from. It's young, it isn't mainstream physics, and the paper behind this series is a preprint: shared for discussion before independent experts have checked it.¹ I also founded the institute, so I'm not a neutral party. Weigh my enthusiasm accordingly.

The universe can't stop taking notes

Take a sip of coffee. Ten minutes later, take another sip.

It's colder.

How do you know?

"Colder" isn't a fact about the coffee in your mouth right now. That coffee just has a temperature. "Colder" is a comparison. Colder than what? Colder than the earlier sip. And the earlier sip doesn't exist anymore. You drank it.

So the only way to know the coffee got colder is that something kept a note about the earlier sip: your memory. Without that note there's no "colder." There's just "is."

Recognition Science starts from three plain facts like that one:

1. Things can be told apart. Hot isn't cold. Here isn't there. This happened, and then that happened.
2. Comparing two things needs information about both. Colder than what? You need the earlier sip and the later one.
3. Checking a note is a new event. When you remember the earlier sip, the remembering is something that happens. It doesn't change the earlier sip. It adds a new moment after it.

"Recognition" is our word for the most basic act there is: one thing registering a difference in another.

Your memory is one note-keeper, and a leaky one. But look around and the world is keeping notes too. A footprint in mud is a note about a foot. A tree's rings are notes about its summers. The starlight reaching your eye tonight is a note the star wrote long ago.

Recognition Science's starting premise takes that all the way. The world keeps a note of every event, in one shared record, and no event ever reaches back and changes an old note. That's a premise, not a result, and I want to be straight about it. I can't prove it to you in a blog post. What I can do is show you what follows from it, which turns out to be a lot.

We call that record the ledger, like a bookkeeper's ledger: entries go in one after another, and they stay.

Things the ledger does not have: an eraser. A delete key. White-out. A "just kidding."

The ledger also has no sense of drama. It has never once skipped a line because nothing interesting happened. Every dull afternoon in the age of the dinosaurs is in there, line by line, in exactly the same ink as the day the asteroid hit.

And there's no bookkeeper, no little guy in a green visor writing it all down. The writing isn't done to events. The writing is the events: when two things bump into each other, the bump is the entry. So writing is an act. Things don't drift into the record by sitting still. A notebook left on a desk doesn't fill itself in.

Still, the ledger has such a strong personality that I'm going to draw it anyway. Meet the Ledger. It's a cartoon (nobody is holding the pen), but if the record of everything had a face, it would be this one: unflappable, very thorough, and armed with exactly one response to anything that has ever happened.

The asteroid that ended the dinosaurs? Noted. The dinosaur that yawned the Tuesday before? Noted, same ink. The coffee you just sipped? Noted.

So here's the first big claim, with its "if" attached:

If the ledger is real, the past isn't gone. It's written down, in pen.

Your seventh birthday party is a stretch of lines in the ledger, and it reads exactly the same today as it did the moment it was written. (What that means for time travel is Part 2's business.)

One ledger, eight billion insides

Now back to the headache.

If the ledger is everything that happens, then your inside has to be in there somewhere. There's nowhere else for it to be: there's no "outside the record" for it to come from. So Recognition Boundary Theory makes a bet, and then goes looking:

Every point of view is a pattern inside the one ledger.

Which patterns? The rest of this post takes four questions in order:

• What lasts? Almost everything is passing through. A point of view has to be something that stays itself.
• Where could experience live? An older test for a complete moment of experience, and what happens when you apply it.
• What does your own record tell you? How your own history sorts out which kind of pattern you are.
• What are the walls? What separates one history from another, and why you ended up in yours.

Then, at the end, the biggest leap of all: whether everything has an inside.

What lasts?

Where do you even start looking? Small. As small as it gets. In the theory, the tiniest moving part of the ledger is a pair of clocks, and they're not a metaphor: the theory treats them as the basic step by which entries get written. (Which physical things in the world actually behave like them is an open question, and so is whether you're built from them.) They're small enough to check completely, so when we ask "what lasts?", we get an exact answer instead of a hunch.

Picture two tiny clocks joined by a loop of wire. I'll call them Left and Right, but those are just names, like "first" and "second." They aren't places. Each clock is either holding a token (call it full) or not (empty). Every tick, three things happen:

1. The pass. Each clock receives whatever the other one was holding: a token, or nothing.
2. Keep or flip. Each clock either keeps what it received or flips it. Flipping turns a token into nothing, and nothing into a token.
3. The flow. Look at what the clocks held when the tick began. If one was full and the other empty, one unit of flow goes round the loop: a flowing tick. If both were full, or both were empty, nothing goes round: a silent tick, the machine's version of an awkward pause.

Each tick, the ledger writes one entry: whether each clock kept or flipped, and which way the flow went, if it went anywhere. (Noted.)

Each clock has a setting that tells it whether to keep or flip. One complication is coming, and I'll tell you where: in a minute, when two clocks disagree. First, the easy part. You're Left. You're full, and Right is empty.

Both set to flip. Tick. You receive Right's nothing and flip it, so now you're full. Right receives your token and flips it, so Right is empty. One unit of flow went round. And look where that leaves you: full, with Right empty, exactly where you started. Next tick, the same. And the next, forever. Call it a spin.

Both set to keep. Tick. You receive nothing and keep it, so you're empty. Right receives your token and keeps it. The token has hopped across, and flow went round. Next tick it hops back to you, and the flow goes the other way. Forever. Call it a swing.

Neither one ever has a silent tick. Hang on to that.

Now let the settings disagree. You flip, Right keeps. Tick 1: you receive nothing and flip it, so you're full. Right receives your token and keeps it, so Right is full too. Both full. The next tick is silent, and here's the complication.

Every setting is a specialist. It's tuned for one kind of tick, and it only knows its own job. The flip and the keep you've been watching are tuned for flowing ticks: on a flowing tick they move for sure. On a silent tick they're out of their depth, and they do what specialists do outside their field. They guess. Each clock tosses a coin to decide whether to flip or keep. And two rules about tuning: a silent tick retunes every clock to the other kind, and a flowing tick retunes nobody. (These rules weren't invented for this post. They're the basic step as defined in an earlier paper.)

Here's the disagreement, tick by tick:

That last state has a name: the wobble. The clocks are lopsided, one full and one empty, but at least one of them is tuned for silent ticks, so it's tossing coins, and from then on each tick it's even odds whether flow goes round or the tick goes silent.

So a setting is really two things, a move (flip or keep) and the kind of tick it's tuned for. That makes four settings in all:

That's the whole machine. Each clock can be full or empty with any of four settings, eight ways to be, so the pair has 8 × 8 = 64 ways to start. The math runs all 64 (the preprint goes through every case). Punchline first: only four never wobble.

Almost everything falls apart

Here's the census.

You can check the first number yourself. Half of the 64 starts, 32 of them, begin lopsided. In 24 of those, at least one clock is tuned for silent ticks, so they're wobbling before anything happens. Another 24 start alike with a clock tuned for flowing ticks, so their very first tick is silent and the coins come out at once. By tick 3, all but four have caught some of the wobble: at least one way their coins can land lets it in.

If a pattern isn't wobbling yet, there's exactly one way in: a silent tick. A flowing tick retunes nobody, so it can never hand a clock the wrong tuning. Only silence can. And a wobbling pair keeps producing silent ticks, which retune more clocks, which make more coin tosses. Silence breeds the wobble, and the wobble breeds silence.

The slowest of the 60 take three ticks. One of them is the disagreement with a single tick of run-up: start both clocks empty, you set to flip and Right to keep, both tuned for silent ticks. Tick 1 is silent, which is exactly their job, so both are sure: you flip nothing into a token, Right keeps its nothing, and the silent tick retunes both for flowing ticks. Now you're the disagreement from before: tick 2 fills you both, and tick 3 is silent. Coins.

Two perfectly predictable ticks, then a coin. It's the new hire who's flawless for exactly two days.

Meet Gary. Gary is a drummer with the wobble: before each beat, a coin decides whether he plays. He can sound fine for a while, because lucky streaks happen. Keep listening and the gaps show up.

Gary is not getting the gig.

So which patterns never go silent at all? You can work this one out yourself, with nothing but the table:

• The pair has to be lopsided right now, or this very tick is silent.
• Neither clock can be tuned for silent ticks, or it's tossing coins, and the next tick might be the silent one.
• The two clocks have to agree, both flip or both keep. You saw what happens when they disagree: the next tick fills both clocks, or (with the token on the other side) empties both.

That leaves two rhythms, the spin and the swing, each in two versions: the token starting on the left or on the right. Two times two: four patterns. Since they never go silent, nothing ever retunes them, so every move they make stays sure, forever.

Out of 64 ways to start, those four are the ones that last. The other 60 don't vanish. They just can't hold a beat: they keep stuttering, going quiet and starting again.

I'll admit this is the moment the toy stops feeling like a toy to me. Sixty-four possibilities, one simple machine, and the only survivors are rhythms. If you take one thing from this post, take this:

What lasts isn't stuff. It's rhythm.

By rhythm I don't just mean regularity. A heartbeat on a hospital monitor is regular, and a regular heartbeat doesn't prove anyone is home. Regular isn't enough. A lasting rhythm is one that never goes silent: its own record never loses track of it.

You already half know this. Most of the stuff you were made of as a kid has long since been swapped out; the material in you turns over constantly. Yet something has been you the whole time. This theory's candidate for that something isn't a lump of matter. It's a rhythm that lasts.

At this point a small voice in the back of your head is clearing its throat. Let's give it a name and a seat: Yeah-But. Yeah-But has never let a big claim through without an objection, and he's earned a hearing.

"Yeah, but I'm not a pair of tiny clocks."

Fair. Here's what's worked out: when many pairs are linked into a web, sharing clocks, the same sorting happens for the web as a whole, and what lasts becomes a property of the whole connected web, not of any one pair. Here's what isn't: whether a person is a pattern of this kind, built from enormous numbers of these pairs. That's the biggest open piece of this work. Everything I say about you from here on assumes it.

Where could experience live?

Recognition Science counts time in cycles of eight ticks. That comes from elsewhere in the framework, and I'll take it as given. An earlier paper, written before anyone knew which patterns last, used it to propose a test for when a moment of experience is complete: a complete moment is one eight-tick cycle with no silent tick in it. Call it the never-skip test.

You can see why "no silent tick" is a sensible thing to ask for. On a silent tick, the flow part of the entry says "nothing went round," and it says that whether both clocks were full or both were empty. From that part of the record alone, you can't tell which. A silent tick is a blind spot. Eight ticks with no silent tick are eight ticks where the flow record tells you, every single tick, where the token was.

(Does the number eight matter? Not much. Anything outside the lasting four has caught some of the wobble within three ticks, so eight ticks is plenty of time for it to show.)

So: which patterns are certain to pass the never-skip test? The same four. A pattern that's certain to pass even its very first stretch of eight ticks is made of those four and nothing else, and it passes every stretch after that, forever.

What a complete moment of experience needs and what lasts turn out to be the same thing.

"Yeah, but both of those are about silence. Of course they match."

That was my first reaction too, and it's the right one to have, so here's what saves the match. Both conditions are about silence, yes. What wasn't guaranteed is the link in the middle: that silence is the only way the wobble gets in. That's a fact about the machine, and it could easily have been false in either of two ways:

• A flowing tick could have knocked a clock off a setting tuned for flowing ticks. Then patterns could fall apart without ever going silent, and the test would pass things that don't last. The machine doesn't do that: a flowing tick retunes nobody.
• A pattern could have gone silent on a schedule, say on every even tick, without ever wobbling. Then it would last, and the test would reject it. The machine doesn't do that either: a scheduled silence always lets the wobble in.

And nothing guaranteed that anything at all would pass for certain. Four patterns do. So the match isn't one idea counted twice. The requirement someone wrote down for a complete moment of experience turns out to be the exact requirement for lasting, for a reason that lives in the machine, not in the test.

Now a leap, with its status first. The math shows only this: these four patterns are present at every tick and leave no blind spots, which is what the test asks of a complete moment. It can't show that there's anything it's like to be one. My bet is that there is. Experience is real, it has to live somewhere in the world, and this is the most natural place the ledger offers. That's a bet, not a theorem.

If the bet is right, you are one of the rhythms the universe never lets skip.

What does your own record tell you?

Here's the question that matters most for you: if almost everything falls apart, how do you know whether you're one of the lasting ones?

Start with a wrinkle. Most patterns aren't neatly one of the four, or neatly not. In this machine, as in quantum physics, a pattern can be partly one thing and partly another at the same time, a bit like a chord is two notes at once. (That's a quantum idea, and I won't unpack it here.) A pattern can be partly a lasting rhythm and partly something else. Call how much of it is lasting its lasting share.

The preprint shows that such a mixture's record comes out exactly as if a coin had been picked at random before anything started: a trick coin with heads on both sides, picked with the lasting share's chance, or an ordinary coin otherwise. Each tick writes heads if something flows and tails if the tick is silent.

• The four lasting patterns are trick coins. They never come up tails.
• Everything else comes up tails sooner or later.
• A mixture is a coin you can't inspect. If its lasting share is 30%, there's a 30% chance you're holding the trick coin.

Flip it. Heads: a bit more likely to be the trick coin. Heads again: more likely still. If an ordinary coin lands heads half the time, every heads halves the odds that you're holding an ordinary one. One tails, and it's over: not lasting, case closed.

In the ledger, nobody has to do the flipping. The pattern's own record does it, tick by tick, and settles the question.

And it plays fair. A mixture with a 30% lasting share ends up settled as "lasting" exactly 30% of the time. The flips settle the question without ever tilting the answer, the way flipping a coin can settle whether it's the trick coin but can never turn it into one.

Your own record settles what you are, and it never tilts the odds.

One more wrinkle. No fixed number of flips settles it for everyone. An ordinary coin can land heads ten times in a row: about a one-in-a-thousand chance, but it happens. In the ledger, too, a pattern that isn't lasting can impersonate one for a while. Short records can be fooled. Long ones almost never are: every extra tick halves the chance of a fake, and no fixed length rules one out for every pattern. Only the endless record can't be fooled at all.

What are the walls?

So far we've run the ledger forwards. Now run it backwards.

You can, one tick at a time, and the entries are what make it work. Each entry says what each clock did: kept, or flipped. So if you know what a clock holds now and what it just did, you know what it received, and what it received is what the other clock was holding a tick earlier.

Try it on the spin. Now: you're full and Right is empty. Last entry: "Left flipped, Right flipped, flow went round." You flipped what you received and ended up full, so you received nothing: a tick ago, Right was empty. Right flipped and ended up empty, so it received a token: a tick ago, you were full. Same as now, one tick earlier.

Since you can always rewind exactly one tick, you can rewind all the way to the first moment. So every page of the ledger, meaning what the clocks hold now plus every entry so far, has exactly one trail back.² It carries its starting arrangement with it, which clocks were full at the very first moment, like a passport stamped at birth. And no event can change the stamp: if two histories that started from different arrangements ever landed on the same page, rewinding that page would have to reach two different starts, and rewinding only ever reaches one.

That's what the walls are. Nothing blocks the way. There's simply no page two differently stamped histories could share. The walls come straight out of the bookkeeping, and they say which rooms your story can happen in, not what happens in them.

Two things follow.

The walls went up at the very first moment. Which history you're in was fixed by how it started. What happens inside it was not.

No fair rule chose where your history started. Picture yourself stepping off a hotel elevator into a long hallway of identical doors, holding a note that says "go to the special room." Which one? They're all the same from here. The ledger's laws are in exactly that position, and the doors are the possible starting arrangements. A fair law can't tell which clock had the token, since Left and Right are only names (and it turns out it can't even tell "full" from "empty"). The most it can do is sort the doors into two kinds: the ones where the clocks started alike and the ones where they started different. It can pick a kind of door. It can never point at one door and say "that one."

Your walls were set at the very first moment, and no fair rule chose them.

So why am I me?

Which brings us to a question that sounds as if it can't possibly have an answer: why am I me, and not somebody else?

The flag first: this applies the clock results to you, so it assumes a person is a pattern of this kind. With that said, here's the answer the picture gives.

Nothing assigned you to you. Nothing that happened later did: no event carries a history across a wall, so no birth, no hospital mix-up and no cosmic lottery along the way ever dealt you in. And no fair law could have picked you out. That's the hallway.

The question moves, and it stops. Which starting arrangement your history began from is a plain fact about the first moment. No rule picked it; it's simply how things began. Asking why it was that one is like asking why the first moment was the first moment. The question doesn't vanish, but it moves to the one place where there was never going to be a further answer.

That still helps. It tells you there's no hidden mechanism you've missed, no dealer behind the curtain. And it gives you something solid: since nothing that happens can carry a history across a wall, nothing that happens can ever make you somebody else.

It isn't fate, either. The walls say which rooms your story can happen in, not what happens in them. What comes next is genuinely open; as you'll see in Part 2, the present doesn't even contain it.

Is everything a little bit awake?

The usual picture of consciousness goes like this: a vast dark warehouse of matter where, here and there, by some lucky accident of chemistry, a light flickers on. Brains. Little lamps in the dark. The rest of the universe, apparently, is furniture.

I think that picture is missing something, and I'll put the premise first, because the framework adopts it rather than deriving it: every recognition event has two sides. An outside, which is what it does and what you could measure. And an inside, which is what it's like. Not two things glued together, but one event, seen from without and from within. That's the old idea that experience goes all the way down; philosophers call it panpsychism.

The main alternative is that experience switches on only in certain complicated things, like brains. My trouble with that view is the switch: nobody can say where it is, or why a pile of matter would go from no inside at all to an inside the moment it crosses some line. If the premise is right, there's no switch to explain, and experience stops being a mysterious extra that brains add to a dead universe. And if the premise is right, the machine shows where the inside holds steady instead of flickering: in exactly the patterns the never-skip test picks out.

"Yeah, but then how do all those tiny insides add up to one you?"

That's the hard one, and I don't have an answer. Neither does the theory yet. Philosophers call it the combination problem, and on this picture it's a real gap, not a detail.

So the honest summary: the premise is adopted, the switch problem is gone, the combination problem isn't, and one step is still open, said plainly: showing that the inside of the activity that keeps a pattern lasting is actually felt.

Conjecture, in one line: experience is the inside of everything that happens, so consciousness is everywhere, and it holds steady in the rhythms that last.

So what are you?

Here's the honest version, sorted.

Shown, in the theory's smallest machine: almost everything falls apart, a few rhythms last, the test for a complete moment picks out exactly those rhythms, a pattern's own record settles which kind it is, and the walls between histories went up at the very first moment.

Bet: that you're a pattern of that kind, and that the lasting rhythms are where experience lives.

If the bet is right, the answer to the headache question is the theory's opening bet: every point of view is a pattern inside the one ledger. You're not a lump of stuff that happens to light up. You're a rhythm the universe never lets skip, with your own record settling, tick by tick, what you are. And you've never felt anyone else's headache because an inside isn't a public thing floating in the room. It's the inside of a pattern, and theirs is a different rhythm from yours.

Next time: if every moment is still written down, where did yesterday go? And can you go back and read it?

(The Ledger would like you to know that it noted you reading this far. It notes everything. Don't take it personally.)