If We're All One, Why Can't I Feel Your Headache?

Sam is sitting across the table from you with two fingers pressed against her temple. She's had a headache since breakfast, and it's a bad one.

You feel nothing. You feel the chair, the coffee and a mild Monday boredom. Not a flicker of Sam's headache.

Now suppose a friend leans over and tells you, very gently, that we're all one. One consciousness, looking out through eight billion pairs of eyes. Everyone, everything, one.

Fine. Then why is Sam the one with the headache?

Anyone who says "we're all one" gets asked this sooner or later, usually by somebody holding an aspirin. It's the right question, and it has an exact answer. That answer also settles the bigger question behind it: is there one consciousness behind everything?

The short answer

Here's the whole answer in five steps. The rest of this post takes them one at a time and shows how we know each one.

1. Felt everywhere is not one consciousness. Every event is felt, because every event has experience: what the event is like. But "every event is felt" doesn't say how many consciousnesses do the feeling. It's true of one, and it's true of billions.
2. Sam's headache is Sam's. It's an event in her rhythm, and you're a different rhythm. The equation for the link between any two consciousnesses depends only on how much room each one takes up, never on what it holds. And when news of her headache does reach you, taking it in is a new event in your own record.
3. One ledger, exact lanes. Reality's record is one thing, and it's built with seams in it from the first page: lanes that never trade weight. One ledger isn't one blend.
4. A whole that keeps you shares ownership. If a whole owns every experience and you still own yours, then Sam's headache belongs to Sam and to the whole at once. Give every experience a single owner, and the whole takes everything and you take nothing.
5. Is the whole itself a consciousness? That's the one question left. The math says exactly what would settle it.

Why this matters. "We're all one" often arrives bundled with "so you're not really here." Step 4 takes the bundle apart. A whole that owns every experience can keep every consciousness in it. What would erase you is giving each experience only one owner. Reality can be one ledger, with every event felt, and still contain eight billion people who each have a consciousness of their own.

Previously

Here's what you need from Part 1 and the coffee mug post, in about a minute.

• Reality is a permanent record. Every event is written down, and nothing is ever erased. We call it the ledger. If it had a personality, its one response to everything would be Noted.
• One tiny process writes it. Two units pass a bit back and forth, and each pass is one event.
• Of the process's 64 starting states, exactly 4 never break. The other 60 fall into coin-flip randomness within three ticks. (Gary, the drummer who flips a coin before every beat, is what they sound like. Gary is not getting the gig.)
• A lasting rhythm is a consciousness. A moment of consciousness is eight unbroken ticks, and only those 4 rhythms deliver one every time. A person is a web of these two-unit pairs, and a web that lasts as a whole is one rhythm, so one consciousness. You are not your body. You're the rhythm. (The mug post calls a consciousness "a self.")
• Every event has experience. Every event is felt, a bump in a coffee mug included. Experience is everywhere. Consciousnesses are rare.

Here's today's route. I'll stop after each step to zoom out, so you always know where we are, what we've got and why the next step comes next. The Ledger is back to keep the map.

Step 1: Felt everywhere is not one consciousness

Every event is felt, and that doesn't add up to one consciousness. "Every event is felt" and "one consciousness feels all of it" are two different claims, and the first doesn't give you the second.

Here's the cleanest way to see it. Take four events: Sam's headache, a toothache in a dentist's chair across town, a sunset, and an itch on your left ankle. All four are felt. Now ask who's doing the feeling.

One answer: a single consciousness feels all four. Another: four consciousnesses, one each. A third: two consciousnesses, two events each. "Every event is felt" is true in all of them. Nothing in the claim picks one.

You can make that exact. Give Sam's headache to one consciousness and every other event in the ledger to a second one. Every event is still felt, and nobody feels everything. The math builds that case for the ledger's events. It isn't a claim about how reality is divided up. It shows what "every event is felt" leaves open: the number of consciousnesses.¹

Yeah-But, the voice in your head that questions every big claim, clears his throat. "Yeah, but if every event is felt, somebody is feeling all of it."

Somebody is feeling each event. Nothing says it's the same somebody.

So "is there one consciousness behind everything?" is a separate question from "is everything felt?" The coffee mug post answers the second one: every event has experience, a mug's included. This post is about the first.

Experience everywhere does not make one consciousness.

Zoom out. Step 1 is done. Every event is felt, and that leaves open how many consciousnesses do the feeling. Next, and why: the headache. If Sam's headache is felt by Sam, what keeps it from reaching you? Three things, and each one is exact.

Step 2: Sam's headache is Sam's

Sam's headache is an event in Sam's rhythm, and you're a different rhythm. Three doors lead from her headache to you. All three are shut.

Door 1: it isn't yours. Part 1 gave this one: each consciousness is its own lasting rhythm. Sam's headache is an event in hers, an entry in Sam's own stretch of the ledger, the stretch that is her life. Your stretch has its own entries: the coffee, the chair, the mild Monday. This entry isn't among them.

Door 2: the link carries no content. Consciousnesses aren't strangers. Every one of them sits in the same ledger, and sitting there ties any two of them together by a link that keeps them in step. So can the headache ride the link?

Look at the equation for the link. For any two consciousnesses, it depends on one thing about each: how much room it takes up. Swap either one for any other consciousness of the same size, with everything else unchanged, and the link stays exactly the same, whatever is inside them. A pair with a headache in one and a daydream in the other gets exactly the link of any other pair that size.² The link tells you how big. It never tells you what.

Picture a metronome that everyone in a room can hear. It keeps every player to the same beat and carries no tune. The metronome is a drawing of the link: it keeps time and nothing else.

Door 3: a reading is a new event. Sam winces. She says, "It's a bad one, eight out of ten." Her face and her words are entries in the ledger, and your eyes and ears read them. Part 1's third plain fact applies: checking a note is a new event. It adds a moment after the one it read. So when news of Sam's headache reaches you, the news landing is an entry in your stretch of the ledger, not hers. It has experience of its own: a wince, a pang of sympathy, a flicker of queasiness. All of that is yours. It's about her headache. It isn't her headache.

You've felt this. Watch a friend stub a toe and you wince too. You really do feel something. What you feel is a wince, in you, about a toe, in them.

A brain scan of Sam is a reading too, and so is a long, vivid description of her migraine. Each one is a new event in the ledger of whoever takes it in.

So what does cross between Sam and you? Information, all day long: faces, voices, texts, scans. What crosses is news about the headache. The headache stays where it was.

Sam's headache is hers, and your wince is yours.

Zoom out. Step 2 is done. A headache is an event in one rhythm. The link between consciousnesses carries how big, never what. A reading of Sam is a new event in you. Next, and why: Door 1 said Sam and you are different rhythms in one ledger. How does one ledger hold separate things at all? It's built with seams, and they're exact.

Step 3: One ledger, exact lanes

The ledger is one record, and it's built in lanes. A lane is a part of the ledger that the ledger's process never moves weight into or out of.

Every history in the ledger starts from somewhere. A history is a starting state and everything the process writes from it, and we'll call the starting state the first page. A start is a snapshot of the two clocks and the loop: which clocks begin full and which begin empty (four possible patterns), and how many units of flow the loop has already carried, counting one direction as plus and the other as minus (any whole number). For example, one start is "both clocks full, loop count 0." The clocks' settings, which Part 1 also counted in its 64 starts, make no difference to the lane.

Every event that actually happens traces back, step by step, to one such start. Events that trace back to the same start sit in the same lane. Four patterns, every whole number: there are infinitely many lanes.

Let's use three and call them A, B and C. A history can start with its weight spread over lanes, where weight is how much of the history sits in a lane. Say half of it starts in lane A, three tenths in lane B and a fifth in lane C. (Made-up numbers, for a worked example.) Run the ledger's process for a billion ticks. How much weight is in each lane?

Fifty percent, thirty percent, twenty percent. Exactly the same, at every tick. No event the ledger can write moves weight from one lane to another, and nothing built out of those events can either. A history with no weight in lane C never gets any there. Not approximately: exactly. No environment is involved and nothing is averaged.³

Two more facts about lanes.

• The first page settles it. Which lanes a history sits in is fixed at the start, and nothing the ledger writes can change it.
• Spread looks like a coin flip. Every measurement the ledger's events can make gives a history spread across lanes the same averages as a coin flip that picks one lane: A with probability one half, B with three tenths, C with one fifth.

(Lane B would like it noted that it's not lane A. Noted.)

A lane isn't a person. It's a part of the ledger, and a lot goes on inside one. You are the lasting rhythm the ledger keeps going there. So the lanes don't say "Sam gets this lane and you get that one." They say something about the ledger itself: it's one record with exact seams running through it from the first page. Nothing at the bottom is blended, and nothing has to be walled off afterward.

Everything that has ever happened, from the first page to your breakfast, sits in lanes whose weights no event has ever moved.

One ledger, exact seams.

Zoom out. Step 3 is done. The ledger is one record built from lanes whose weights never move, so separation inside it is exact, from the first page, with no wall added later. Next, and why: the word "whole." If the ledger is one thing built of exact parts, what would it take for the whole to hold every experience and still leave you you?

Step 4: A whole that keeps you

A whole that owns every experience can keep every consciousness in it, but only if ownership overlaps.

First the words. The whole is the ledger taken all together: every lane, joined. (Part 3 called it the shared field.) An experience can have an owner: a consciousness it belongs to. Sam's headache belongs to Sam. Now suppose the whole is a consciousness, one that every experience in the ledger belongs to. That's what "one consciousness behind everything" would be. Does it leave room for Sam?

Take three people: Sam, you, and Pat, who's watching a sunset somewhere. Three experiences: Sam's headache, your warm coffee, Pat's sunset. The whole owns all three. The question is who else does.

One owner each. Suppose every experience can have only one owner. The whole owns all three, so the whole is the only owner of all three. Sam owns nothing, you own nothing, Pat owns nothing. Or, to put it exactly: anyone who owns anything is the whole. One consciousness, three experiences, and no you.

Two owners each. Suppose an experience can have two owners. Sam's headache belongs to Sam and to the whole. Your coffee belongs to you and to the whole. Pat's sunset belongs to Pat and to the whole. The whole holds all three, and Sam, you and Pat each keep yours. Nobody is erased.

That's exact. Any whole that owns every experience, while some other consciousness owns an experience of its own, has to share ownership.⁴ Containing everyone doesn't erase you. Exclusive ownership does. I find that reassuring.

You've seen the shape before, in a stadium wave. Say 70,000 people, one wave going round the ground. When you stand up, that's your event. It's also an event of the wave, because the wave is made of everyone standing up in turn. One event, two owners. The wave doesn't erase you: you're still the one who stood, and the person next to you is still the person next to you. The wave is a drawing of overlapping ownership and nothing more. It doesn't feel anything.

The ledger already has this shape. Every event belongs to its lane and to the whole, and those are different things. Two lanes share no event. Parts of the ledger aren't consciousnesses just by being parts, and that's Step 5. But the pattern is the one a whole consciousness needs: nested, never exclusive.

Yeah-But is back. "Yeah, but if the whole owns Sam's headache, doesn't the whole have a headache?"

That's the question Step 5 is about.

A whole can hold Sam's headache without you holding it.

Zoom out. Step 4 is done. A whole that owns every experience and leaves anyone else owning anything shares ownership, so it can hold Sam's headache while you don't. Next, and why: the last step, and the one question left. Is the whole a consciousness that every experience in the ledger belongs to?

Step 5: Is the whole a consciousness?

This is the question that's left. Here's what it is, and exactly what's missing.

The whole, as a piece of the ledger, is there: every lane joined, one piece bigger than any lane. What's open is whether the whole is also a consciousness: one lasting rhythm that every experience in the ledger belongs to. Part 1 gave the rule for a person: a web that lasts as a whole is one rhythm. Whether the whole ledger counts as a web like that is the same question at the largest size. Philosophers call the question of how several consciousnesses can make up one bigger consciousness the subject-combination problem.⁵

The math says two things about what it takes. I'll draw each consciousness as a room that holds a group of experiences.

Being connected is not enough. Here's a small world. Its experiences are numbered 1, 2, 3 and on forever. A consciousness in it is any finite group of those numbers: {1, 2, 3} is one, {4, 17} is another, {5} is another. Every experience belongs to a consciousness. Every finite group of experiences belongs together to a consciousness, because the group is one. And no consciousness holds all of them: pick any finite group and the next number is missing from it.

This small world isn't ours. It shows that "every group has an owner" and "one owner has everything" are different claims, and that the first doesn't give you the second.

What would make a whole. The math has an exact test. Suppose the consciousnesses are arranged so that any growing line of them ends at a consciousness instead of running off the edge (the math word is compact), and suppose each experience's owners include their own limits. Then a whole exists exactly when every finite group of experiences has a common owner.⁶

Does reality meet those conditions? Two things have to be settled in the physics itself. Every finite group of actual experiences, Sam's headache, your coffee, Pat's sunset and as many more as you like, has to belong together to one actual consciousness. And the actual consciousnesses have to be arranged with no missing last room. Both are about actual experiences and actual owners in the physics. That last step is still being worked out.

Whichever way it comes out, Sam's headache is Sam's. You're a consciousness, so if the whole is one too, it shares ownership of its experiences with you, and Step 4 leaves it no other way. If the whole isn't a consciousness, no consciousness feels everything at once.

Either way, the ledger is one, every event in it is felt, and every consciousness in it is intact.

Zoom out. Step 5 is done. The whole is there, as the ledger itself. Whether it's also a consciousness comes down to those two conditions in the physics. Next, and why: nothing is left but the whole trip, in one breath.

The whole trip, in one breath

Reality is one ledger, written by one process, and every event in it is felt. That makes experience universal, and it doesn't make one consciousness. Sam's headache is an event in Sam's rhythm. It's hers because you're a different rhythm, because the link between consciousnesses carries how big and never what, and because reading Sam's face is a new event in your own record. Underneath, the ledger is one piece with exact seams in it: lanes whose weights no event has moved since the first page. A whole that owns every experience and keeps every consciousness shares ownership, so Sam's headache is hers and the whole's, and your coffee is yours and the whole's. Whether the whole is also a consciousness is the one step left: it needs every finite group of experiences to have a common owner, and the owners arranged with no missing last room.

Billions of consciousnesses, one ledger, every event felt, nobody erased. That's how reality is built.

(The Ledger would like you to know that it noted Sam's headache and your lack of one, in the same ink. It also noted your wince. It has never once mixed up two entries.)