Will Humanity Survive? No Law Decides It. Going On Has an Exact Condition.

You've seen the lists. The ways humanity ends: a nuclear war, a pandemic worse than the last one, a planet that warms past what our cities were built for.

Each list is a story about what's coming for us. Each one ends with the question under the headline. Will we make it?

Nobody finishes one feeling better. A list can't answer that question. It names the threats. It doesn't say what going on depends on.

So ask that instead, and start small. You have savings and a paycheck. Every month you spend a little more than the paycheck brings in. Nothing dramatic happens. The balance slides a bit each month, and for a long time you don't notice. Then one month the savings are gone.

How big were the savings? That only decides when. Double them and you last twice as long. You don't last forever. Spend no more than the paycheck and the account never runs dry.

That's arithmetic, and it's the shape of the whole answer. The bank account is a drawing of a rule in physics. This post gives the rule, says where the bill comes from and who pays it, and shows why nobody can read the ending ahead.

The short answer

No law of physics decides it. The laws say what any next entry in reality's record has to satisfy. They never say which entry comes next. So whether humanity goes on isn't written anywhere, and nobody can read it ahead, because a moment that hasn't happened has no content yet.

What physics does fix is the arithmetic of going on. Anything that runs on a reserve, a budget and a standing bill goes on for good exactly when its reserve starts above zero and what comes back each cycle covers what it spends. (A cycle is one round of the accounting, a month in the bank drawing.) A bill that beats the budget by any amount, every cycle, empties any finite reserve, however big. The size of the reserve only sets when. And a group goes on only when every member's own bill is covered. A lower total doesn't do it.

Whatever happens, nothing we've done is ever erased. Every life lived stays written, and the past still exists. Physics already agrees on the part it covers: its basic laws never destroy information about the past.

Step 2 says exactly what is derived, and what isn't yet, when the arithmetic is applied to humanity.

Why this matters

The usual question asks for a forecast, and nothing of that kind is written anywhere to be read. What the physics gives instead is the shape of the question. Going on has a condition, and the condition is a comparison: what comes back against what's spent, one member at a time.

That takes two stories off the table. "We're doomed" has no law behind it, and neither does "we'll be fine." And it says what a big stockpile can't do. Against a bill that beats the budget, a reserve only buys time.

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

1. No law decides it, and nobody can read it ahead. From every balanced record the laws allow more than one next entry at the same price, no disturbance tips the tie, and the present holds exact odds, never the answer.
2. Going on has an exact condition. A member with a reserve R, a budget B and a bill c goes on exactly when R is above zero and B is at least c. A bill that beats the budget empties any reserve. A stockpile isn't an income.
3. Holding a relationship out of balance costs a bill every cycle, on both ends. A move that looks zero-sum in amounts adds cost: 2 and 1/2 multiply to 1, and the relationship costs 1/4.
4. A group goes on only when every member does. Lowering the total can run one member's reserve out.
5. Waiting costs, and nothing makes anyone repair. In the case the code works through, a strained relationship left alone doubles every cycle, and its bill outruns any budget. The code can require repair. It can't make anyone do it.
6. Nothing we do is ever erased. The record only grows. Even a last day would go in as one more line.

What this answer stands on

Three facts, each with its reason. What You Are goes through the record at more length, and What Do We Owe Each Other? works out the code. This is what this post needs.

Nothing that happens is ever erased. Every event leaves a complete trace, and the full record of what happened is part of reality now. The past still exists. The reason starts in known physics: the basic laws never destroy information. In quantum mechanics that's called unitarity. The present fixes the past exactly, and running the laws backward recovers every earlier state. That's why physicists treat the black hole information problem as a real problem: losing information would break the laws.¹ Our work at the Recognition Physics Research Institute adds the record's own rule: it only grows. Each new entry is added with every earlier entry kept, and writing a new entry never alters an earlier one.²

Every entry is a relationship between two things, and a relationship has a cost. Every event is one entry in the record. The smallest thing that can happen is one thing being told apart from another, a single yes or no. You're doing it right now: every measurement and every perception tells one thing from another. Telling two things apart takes information about both of them, so an entry is a comparison of two things. I'll call it a relationship. It's carried as one number: one amount divided by the other. When the amounts match, the number is 1. I'll call that balance. Every other number costs, and the cost measures how far the two sides are from matching. Add the number to its flip (1 divided by the number), halve the sum, and subtract 1:

J(x) = (x + 1/x) / 2 − 1

Check the third row: 2 plus its flip, 1/2, is 5/2. Half of that is 5/4, and 5/4 minus 1 is 1/4. For 1/2 the flip is 2, so the sum is the same and so is the cost. It's one relationship read from its two ends. Nobody picked the formula. The cost has to be zero when the two sides match, grow as they differ, and come out the same whichever side you read from. Add the rule for how the costs of combined comparisons add, and one calibration (how sharply the cost rises near balance), and exactly one formula is left.³

The record is kept twice, and one code reads it. Each relationship is recorded twice, once by each of its two ends, on that end's own books. Nobody writes in another's books. A record is true when it gives the relationship's actual number. Anything that is an end of a relationship is a participant, and in a group I'll call it a member. A member's burden is the cost of the relationships it's an end of, each counted in full, while the record's own total counts each relationship once. Acts change the books, and the clauses of the code in our paper The Moral Code say which acts are admissible. Two of them matter here: after an act, every record of every relationship has to be true, and an act may move a relationship only when both of its ends write on it. The clauses aren't chosen. They're what a record kept twice admits. The both-ends clause rests on one step that isn't derived yet: that each record holds the relationship's one exact number.⁴ Of the admissible acts, the code permits exactly those that leave the least total cost on the complete record. That's love's act. The code judges acts. It makes no one do anything.

Nothing moves a relationship between acts: a relationship changes only through what someone sends, and sending is an act. Step 5 says what that means for waiting.

Step 1: No law decides it, and nobody can read it ahead

The laws say what any next entry has to satisfy. They never say which one comes next. So no law fixes whether humanity goes on.

Here's how we know, one fact at a time.

Keeping the past doesn't fix the future. Unitarity preserves information about the past. It doesn't settle which outcome gets recorded next. In quantum physics the state evolves exactly, but the answer a measurement records isn't fixed in advance. Bell tests rule out answers set beforehand and carried along by the particles. That rules out local hidden answers. It doesn't by itself rule out every hidden determinism, and that's what the next two facts are for.⁵

The laws leave ties. Start with a record where everything is in balance, and ask what the next entry can be. One allowed entry sets a pair of things out of step by a factor of 2, and it costs 1/4. Another sets a different pair out of step by the same factor, and it costs 1/4 too. Both are allowed by every law that prices and balances the books, and the laws give them the same price. They price both entries to the fraction and pick neither. That holds from every balanced record, however much has been written.⁶

Does something else pick? A tiny disturbance, the way a nudge tips a pencil balanced on its point? No. A disturbance is something that happened, so it's already in the record, and the tie holds from every balanced record whatever the record holds. There's nothing earlier to break it.

Doesn't nature just take the cheapest step? No. The cheapest step is to write nothing, and entries get written anyway.

The present holds odds, never the answer. Everything the present holds about what comes next is a set of exact odds. The law that writes the record gives "write nothing at this step" odds strictly between 0 and 1, never certain and never impossible. A law that fixed the next entry would have to give every possible entry odds of exactly 0 or 1. So no law of that kind is the one the record follows.⁶

And nobody can read it ahead. No reading of any kind returns the content of a moment that hasn't happened. The record holds what has happened, so nothing is written there yet. The address of the next moment exists, because the record keeps running. Its content doesn't exist yet.⁷ So at best a forecast is odds. It can't be the answer, because the answer doesn't exist yet.

One step isn't derived yet: what picks which of the allowed entries gets written. Every act goes in under its author's name. Is Your Next Move Already Written? says exactly where the pick stands, and Time explains where the odds come from.

Next, and why: with nothing written, the useful question is what going on requires. Step 2 gives it exactly.

Step 2: Going on has an exact condition

Anything that runs on a reserve goes on for good exactly when it starts with something in the reserve and what comes back each cycle covers what it spends.

Here's the exact version. Take one member of a group. Give it a starting reserve R, a budget B that comes back every cycle, and a standing charge c that comes out of the reserve every cycle, which I'll call its bill. I'll call one step of this accounting a cycle, and the numbers below count cycles, so they hold however long a cycle lasts. I'll say the member goes on when its reserve stays above zero at every cycle, the starting one included. That happens exactly when

R is above zero, and B is at least c.

The bank account was a drawing of this. The savings are the reserve, the paycheck is the budget, and what goes out every month is the bill. In the physics, the reserve is what a member has left to keep going on, and the budget is what comes back into it each cycle. I'm not saying the reserve is money, and I'm not saying it's energy. What it is, physically, is the open step below.⁸

Here's why it's exactly that. After n cycles the reserve is R + n × (B − c). If B is at least c, that's at least R, so the reserve never falls below where it started. If c beats B by some amount d every cycle, the reserve falls by d every cycle, so it's at or below zero from cycle R ÷ d on, rounded up to a whole cycle. That holds whatever R is.

Let me put numbers on it. I chose a reserve of 1 and a budget of 1/4 a cycle to keep the arithmetic small. They're example values. They aren't humanity's. Here are three members with three different bills. (Step 3 says where bills come from.)

Read the rows. With every relationship in balance the bill is 0, and the budget only adds, so the reserve grows. At a bill of 1/4 the budget covers it exactly, and the reserve holds at 1. At a bill of 1/2 the bill beats the budget by 1/4. The reserve reads 1/4 after three cycles and 0 after four. It's gone at cycle 4, and 1 ÷ (1/4) = 4.

A stockpile isn't an income. Keep that bill and give the member a bigger reserve. A reserve of 2 is gone at cycle 8, and a reserve of 4 at cycle 16. Every line ends at zero. The bigger the reserve, the later it ends.

A reserve is a stock, what's left to spend. A budget is a flow, what comes back each cycle. Drawing on the stock only sets when it runs out. The flow sets whether it does. A bill that beats the budget by only 1/100 a cycle empties a reserve of 1,000 by cycle 100,000, because 1,000 ÷ (1/100) = 100,000. That's a long time. It still ends.

Put humanity on the rule and it says what going on requires: every member's reserve above zero, and every member's budget at least its bill. It can't say whether humanity's bill beats its budget, because the rule doesn't come with the numbers. That last step isn't derived yet: what humanity's reserve, budget and standing bill are in physical terms, how large they are, why each cycle's bill comes out of the reserve, and that a civilization of members runs on this rule. Until it is, every reserve, budget and bill in this post is a chosen example value, and none of it is a forecast.

Next, and why: the bill is the thing to understand. Where does it come from, and who carries it? Step 3.

Step 3: Holding a relationship out of balance costs every cycle, on both ends

Every relationship that sits out of balance costs a standing amount each cycle, and each of its ends carries the whole amount. The bill in Step 2 is the sum of those amounts for the relationships a member is an end of.

Here's how we know. Take a relationship in balance: 1 at one end and 1 at the other, costing 0. Now move it so that one end's number doubles and the other's halves, to 2 and 1/2. I'll call a move like that taking, as Karma Is Real, and It Isn't a Referee does. The word is mine. Both ends have to write the move, because an act may move a relationship only when both of its ends write on it. A lone write moves nothing: someone who writes a change only in their own book leaves that book false, and the code forbids writing it. An act that changed the relationship without the other end's write would be harm, a false entry in the other end's own record, and the code forbids that too.

Count it in amounts, and nothing was made or lost. 2 × 1/2 = 1, so the doubling at one end is cancelled by the halving at the other. It looks zero-sum. Now price it. The relationship at 2 costs (2 + 1/2)/2 − 1 = 1/4. A moment ago it cost 0.

That isn't the luck of moving by 2. For a move by any factor x, the cost is (x + 1/x)/2 − 1, which equals (x − 1)² divided by 2x. That's a square over a positive number, so it's never negative, and it's zero only when x is 1. Every move off balance costs, and the cost climbs faster than the move: 3/2 costs 1/12, 2 costs 1/4, and 4 costs 9/8. A transfer that looks zero-sum in amounts is a strict increase in cost.

Each end carries all of it. A relationship needs both of its terms, so each end is an end of the whole relationship. At 2, one end carries 1/4 and the other end carries 1/4, and the record counts the relationship once, at 1/4. So taking doesn't move cost off your books. It puts the cost on yours too.

A relationship also stays where it was moved until it's moved again, and the record charges it at every cycle it's held out of balance. The Moral Code proves the general fact for a record that decides each relationship's charge from that relationship's own entry alone, the way a comparison reads only its own two terms. Take two histories that agree everywhere except at one cycle, where one costs more. The record charges that excess at every later cycle, undiminished.⁹ That the record reads each relationship that way isn't derived yet.

Now put Step 3 into Step 2. A member's bill is the cost of the relationships it's an end of. One relationship held at 2 costs 1/4 a cycle, which in the running example is the whole budget. Hold two there and the bill is 1/2. It beats the budget by 1/4, and a reserve of 1 is gone at cycle 4. A member that holds more strain than its budget covers can't keep going on its reserve.

Next, and why: a relationship's bill lands on both of its ends. So who has to be covered? Everyone. Step 4.

Step 4: A group goes on only when every member does

A group goes on only when each member's own bill is covered by that member's own budget. A lower total doesn't do it.

Here's how we know. The rule in Step 2 is about one member's own reserve, budget and bill. Each member's bill comes out of that member's own reserve, and that member's own budget tops the reserve up. Our book manuscript, The Moral Code of Reality, applies the rule to two members: both continue exactly when each one opens with a positive reserve and each one's budget is at least that one's own bill.¹⁰ For a group of any size it's the same condition, one member at a time. I'll say a group goes on when none of its members runs out of reserve.

Watch a lower total fail. A member's own load is a relationship too: one number for how heavy the load is, with 1 as balance. Take two members. One carries a load at 4, which costs 9/8 a cycle. The other carries nothing, which costs 0. They meet in the middle, at 2 and 2. Nothing is made or lost, because 4 × 1 = 2 × 2. Of every way to share the load with nothing made or lost, meeting in the middle leaves the least total cost, and Meet in the Middle: What Love Does calls it love. The pair's total cost falls from 9/8 to 1/2. The member who was carrying the 4 now pays 1/4 instead of 9/8. And the member who took on part of the load now pays 1/4 instead of 0.

Say the first member's budget is 1/4 and the second member's is 1/8. The first pays 1/4 and gets 1/4 back, so its reserve holds. The second pays 1/4 and gets only 1/8 back, so it's short by 1/8 every cycle, and a reserve of 1 is gone by cycle 8. The total went down, and one member's reserve runs out. Give both members a budget of 1/4 instead and both go on. Meet in the Middle works the same pair through with other budgets.

The total can fail a bystander too. In Step 5 of Karma Is Real, three people re-route one debt to cut the total cost from 1/2 to 1/3. The third person, who owed nothing and was owed nothing, ends up as an end of two relationships that cost 1/18 each. That example's cost is simplified, as that post says. The code forbids the re-routing unless the third person writes on both of those relationships. The clauses come first.¹¹

So lowering the total isn't the same as burdening no one, and it isn't the same as keeping everyone going.

Next, and why: so far the bill has been held still. What happens to a strained relationship that nobody repairs? Step 5.

Step 5: Waiting costs, and nothing makes anyone repair

In the case the code works through, a strained relationship left alone doubles every cycle. There its bill soon beats any budget, and the record charges every cycle of the wait. The code can require repair. It can't make anyone do it.

Here's how we know. Between acts, a relationship holds where the last act left it, so a strained one stays strained until both of its ends write a repair. The code works through one case where waiting costs more every cycle, the care law. On a relationship the care law runs from that relationship's repair reserve, the store that pays for its repair. (That isn't the reserve of Step 2. That one belongs to a member and pays a bill. This one belongs to a relationship and pays for repair.) A strained relationship is repaired while its repair reserve lasts. In that case, once the repair reserve is spent, the relationship's number doubles every cycle.¹²

Count it. Take a relationship in balance with no repair reserve. Cycle 0, it sits at 1. Then it goes to 2, then 4, 8, 16, 32. Each cycle's bill is the cost of its number.

Check the cycle-3 entry: 8 plus its flip, 1/8, is 65/8. Half of that is 65/16, and 65/16 minus 1 is 49/16. The first doubling costs 1/4, which is the whole budget in the running example. After that each bill is more than double the one before, and the ratio settles toward exactly double. A bill that grows like that beats any budget eventually, because a budget stays where it is.

So in that case a strained relationship has two futures. While its repair reserve lasts, the care law repairs it every cycle, and its bill stays at 0. Once the reserve is spent and nobody repairs it, its bill climbs past any budget, and the record charges every cycle of it, as Step 3 showed. Bringing it back to balance changes it, so both of its ends write the repair. And where an admissible act leaves less cost than doing nothing, the code forbids doing nothing. That's how the code can require an act.

Time doesn't heal a relationship. Two people do.

And nothing makes anyone repair. Everyone already lives under the same cost, and people hold relationships out of balance anyway. The code judges acts. The forbidden act is as possible as the permitted one, and nothing physical stands in its way. The record alone excludes nothing: doing nothing, even where a repair would lower the cost, is possible forever, while the record's charge on it grows without bound. A run of love's acts, which takes the least total cost at each step, keeps that charge bounded on any menu that offers a way down.¹³ The cost doesn't make anyone good. It prices the difference between the runs. What the code asks of each of us is the subject of What Do We Owe Each Other? and How Should We Live?.

Next, and why: one more fact sits under every step so far. Whichever way the ending goes, what happens to what's already written? Step 6.

Step 6: Nothing we do is ever erased

Whatever happens, every life lived stays written. The record only adds lines at the bottom, and every line already written stays exactly as it was. Even humanity's last day, if there is one, goes in as one more line.

Here's how we know. The reason is the one in "What this answer stands on": the basic laws never destroy information, and the record's own rule is that it only grows. Here's what that means exactly. The record is a list, and the only thing that can happen to it is a new line at the bottom. Take a record with three lines, A, B and C, and write a fourth, D. A, B and C read exactly as before. Each is still at its address. The list is one line longer.

So say the worst happens. That's an event, and an event goes in as a line, at the bottom. It doesn't take a single line above it along. Every life that has ever been lived is in the record right now, and no later line can touch it.

That cuts both ways. Every kindness stays written, and so does every harm. A false line stays under its author's name for good. A relationship that ends stays on the record with all of its cost.¹⁴

So the answer to "will we make it?" leaves one thing outside the question: what's already been done. What happens to one person at death is a different question, and What Happens When You Die? answers it. For the end of the whole universe, How Will the Universe End? works through a model world.

What's still open

Four steps are not derived yet. Each is stated once where it matters above, and here.

• What humanity's reserve, budget and standing bill are. In physical terms, how large they are, why each cycle's bill comes out of the reserve, and that a civilization of members runs on this rule. The answer needs this one.
• That the record reads each relationship from its own entry, so that a relationship held out of balance is charged at every cycle.
• That each record holds a relationship's one exact number. The both-ends clause rests on it.
• What picks which of the allowed entries gets written. Every act goes in under its author's name. What picks the act is the step Is Your Next Move Already Written? names.

The other results here are proved in the sources the footnotes name, with their premises stated where they enter.

The whole trip, in one breath

No law writes humanity's ending. The laws price what any next entry has to satisfy and leave ties, the present holds exact odds and never the answer, and a moment that hasn't happened has no content to read. What physics does fix is the arithmetic of going on. A member with a reserve R, a budget B and a bill c goes on for good exactly when R is above zero and B covers c. A bill that beats the budget by any amount empties any reserve, and the size of the reserve only sets when. The bill comes from relationships held out of balance, each costing (x + 1/x)/2 − 1 every cycle on both of its ends, so a transfer that looks zero-sum in amounts adds cost. A group goes on only when every member's own bill is covered, so lowering the total isn't enough. In the case the code works through, a strained relationship left alone doubles every cycle and its bill outruns any budget, so waiting costs. The code can require repair. Nothing makes anyone do it. And through all of it, nothing is erased. Every life lived stays written, and the past still exists.

That's how reality is built. What's ahead isn't written. What's behind never goes.