The Last Step

I. Two Foundations

There are two ways to argue that civilizational trajectories matter more than individual welfare snapshots.

The first: we don't know which moral theory is correct, so we should hedge across all of them by preserving the option space. This is the moral uncertainty move. It says: maybe individual welfare is all that matters, maybe systemic properties matter too, maybe something else entirely — and since we can't resolve this, the rational response is to keep all futures open. Don't lock in.

The second: physics constrains which configurations of organized complexity persist over time, and those constraints are derivable from first principles. This is not a moral theory. It is structural analysis — the same kind that tells you which bridge designs hold and which collapse. It doesn't tell you what to value. It tells you which value-configurations self-destruct.

Both paths arrive at the same destination: preserve the possibility-space, don't lock in prematurely, sustain the conditions for continued complexity. But the foundations have radically different load-bearing capacity. One is a hedge. The other is bedrock.

William MacAskill, in Better Futures (2025), built the most sophisticated version of the first path anyone has produced. He gets remarkably close to the second. He stops one step short.

II. What MacAskill Built

The median effective altruist thinks in QALYs. Individual lives saved, individual suffering averted, individual welfare maximized. The unit of analysis is the sentient being. The metric is subjective experience.

MacAskill goes further. In Better Futures, he introduces the S×F model: the expected value of the future is the product of Surviving (probability of avoiding civilizational catastrophe) and Flourishing (expected value conditional on survival). This is already a departure from pure aggregation — it treats civilizational survival as a variable in its own right, not merely as a container for individual welfare. The structure is striking: Surviving × Flourishing maps onto the thermodynamic requirement that any system maintain both persistence and surplus capacity against entropy. But physics reveals a correction MacAskill's moral philosophy misses. He treats S and F as independent variables — separable, with distinct cause areas. Thermodynamics says they converge: flourishing is maximum safety margin, which is maximum survival probability. A civilization optimized for bare survival (Sparta) strips the surplus capacity that survival requires. S and F aren't two variables to multiply. They're one phenomenon — sustained syntropy — viewed from two angles.

Then he goes further still. He defines value as "the difference that Earth-originating intelligent life makes to the value of the universe" — a framing that is explicitly not reducible to any individual's experience. He acknowledges that "the proliferation of complex systems" and "feats of engineering" might be intrinsically valuable. He notes that a future of happy clones could "fall far short of ideal" — meaning diversity and complexity matter independently of welfare.

His concept of viatopia — a state where existential risk is low, many moral viewpoints flourish, many possible futures remain open, and decisions are made through reflective processes — is not an individual welfare state. It is a civilizational state. A property of the system, not reducible to the properties of its members.

And he worries about value lock-in: the risk that humanity permanently narrows its possibility-space by committing to a value-configuration before it has the wisdom to choose well. His response: explicitly temporary commitments. Don't lock in. Preserve options. Buy time for reflection.

This is genuinely impressive — and it stops one step short.

III. The Axiom He Inherits

The foundational axiom of the rationalist-EA tradition is ontological individualism: the individual sentient being is the fundamental unit of moral analysis. The interest of a community is the sum of the interests of its individual members. Systems, institutions, and civilizations have no value independent of the experiences they produce in individual beings.

This axiom entered through a specific intellectual genealogy. Bentham (1789) declared the community a "fictitious body" — nothing real except the individuals who compose it. Sidgwick (1874) anchored it — ironically, in defense of egoism: "the distinction between any one individual and any other is real and fundamental." Both sides of Sidgwick's unresolved dualism — egoism and utilitarianism — require ontological individualism. Neither questions it. Singer (1975) radicalized it by extending it past the species boundary — only individual sentience matters, not species or ecosystems. GiveWell operationalized it: the spreadsheet has individuals as rows, interventions as columns, QALYs as values.

The axiom was never derived from first principles. It was inherited from the utilitarian lineage and never surfaced as debatable — partly because it seems obviously correct to anyone raised in the liberal-Enlightenment tradition, and partly because the alternative ("the collective is the unit") has a catastrophic track record. The 20th century taught that subordinating individuals to abstractions produces gulags. The axiom functions as an anti-totalitarian firewall.

The rationalist community has partially examined this. Derek Parfit, the most revered philosopher in the EA canon, demolished personal identity in Reasons and Persons (1984). He showed there is no "further fact" that makes you the same person over time — the self is a convention, like a nation. EA followed Parfit faithfully — his demolition supported utilitarian aggregation by dissolving the "separateness of persons" that resists it.

But Parfit's demolition was partial. He went sub-personal — down to experiences as the new atom of value — not super-personal. He never asked whether the self-maintaining process might be the right level of analysis. The person dissolved into a stream of experiences. The stream is still counted individually. The metrics (QALYs, WELLBYs) sum experiences as discrete units — while the system that generates and sustains those experiences across time goes unmeasured. Parfit himself glimpsed what lay above: in §154, he notes Sidgwick's "ideal goods" — the Sciences, the Arts, moral progress — as reasons the destruction of mankind would be a great loss. These are civilizational goods, not individual experiences. He doesn't develop it.

MacAskill inherits this tension. Better Futures gestures beyond it — complex systems, civilizational states, possibility-space — but the operational framework remains consequentialist and welfarist. When he evaluates futures, the default metric is still the aggregate of individual experience. The systemic properties are acknowledged as things some moral theories might value. They are not treated as things physics requires.

IV. The Step

MacAskill's move: "We face moral uncertainty across competing theories. Some theories value individual welfare. Some might value complex systems, diversity, or possibility-space. Since we don't know which theory is correct, we should hedge by preserving all options."

The step he doesn't take: "What does physics require for complex systems to persist? The constraints are derivable from thermodynamics. They are structural analysis, not competing moral philosophy."

The difference looks subtle. It is not.

Moral uncertainty says: maybe systemic properties matter. Physics says: self-maintaining dissipative structures are what persist, and the constraints on their persistence are discoverable. The first is a hedge across theories. The second is a ground truth that holds regardless of which theory you find persuasive.

MacAskill writes: "perhaps some of the following goods are intrinsically valuable: the acquisition of knowledge; the proliferation of life; the proliferation of complex systems; feats of engineering; preference-satisfaction." Read that list again. Knowledge acquisition. Proliferation of life. Proliferation of complex systems. That is sustained syntropy — sustained complexity generation against entropy — stated in different words. MacAskill has already identified the terminal value. He just won't commit to it. The "perhaps" is doing all the load-bearing evasion. If the proliferation of complex systems is treated as one possible value among many — to be hedged across alongside hedonism, egalitarianism, and environmentalism — then it has no more structural weight than any competing theory. It can be overridden by any sufficiently confident moral claim.

But if the proliferation of complex systems is what physics selects for — if the constraints on persistence are the constraints — then it is not one theory among many. It is what remains after all theories have been tested against the survival filter. The bridge holds or it doesn't. Your theory of gravity is irrelevant to the outcome.

V. Why It Matters

Moral uncertainty is fragile. MacAskill himself identifies the vulnerability. He asks: "would you want to risk society being taken over, at some point in the future, by a fascist regime?" His answer is that some lock-in of good values is necessary. But which values? On what grounds? Moral uncertainty provides no answer — it can only say "hedge." The moment someone presents a confident moral theory, the hedge is under pressure. The moment a powerful actor is confident, the hedge is overridden.

MacAskill's moral uncertainty says: preserve the option space. The median EA says: maximize expected QALYs. The QALY-maximizer is more confident, more tractable, more legible to funders. In a contest between "preserve options because we're uncertain" and "save this many lives because the math is clear," the math wins. The hedge dissolves under operational pressure.

Physics-grounded constraints don't dissolve. "This civilizational configuration will deplete its capital stocks and collapse" is a prediction — derivable from the same physics that tells you a bridge will fail under excess load.

The AI alignment community already accepts this logic. Instrumental convergence: any sufficiently intelligent agent, regardless of terminal goals, will converge on self-preservation, resource acquisition, and goal-integrity — because physics constrains what any agent needs to achieve anything. Nobody objects to instrumental convergence on moral-uncertainty grounds. Nobody says "well, maybe some agents don't need self-preservation — we should hedge." The derivation is accepted because it stays on the "is" side of the is-ought gap. It describes what's physically required, not what's morally preferred.

The step is one hop: apply instrumental convergence to civilizations. Physics constrains what any civilization needs to persist, regardless of what that civilization values. The constraints are the same: maintain your entropy-pumping capacity, defend your capital stocks, sustain your complexity-generation capability. The specific value-configuration is your business. The boundary conditions are physics.

MacAskill's viatopia — low existential risk, many viewpoints flourishing, many futures open, reflective decision-making — is what you get when you solve for these constraints. He arrived at it through moral uncertainty. It can also be derived from thermodynamics: flourishing is maximal safety margin, and the safety margin is what physics requires for persistence through unpredictable shocks. The derived version doesn't need the hedge. It holds regardless of what anyone believes about morality.

VI. The Zombie Axiom

The zombie axiom — Parfit's partial demolition, followed downward to experiences but never upward to systems — determines everything downstream. If the individual is the unit, then value is aggregated individual welfare, cause prioritization defaults toward measurable individual-level interventions, scope sensitivity is a mathematical requirement, and "the proliferation of complex systems" is at best a secondary consideration — one moral theory among many, to be hedged across.

If the self-maintaining system is the unit — not the momentary experiencer — then the landscape inverts. Value is the capacity for sustained complexity generation. Cause prioritization favors whatever maintains that capacity. Scope sensitivity is calibrated to actionable coordination range, not to the mathematical ideal of an isolated agent facing the universe. And the proliferation of complex systems is not one theory among many — it is what persistence looks like, derivable from thermodynamics. This is not the collectivist move. Individuals remain load-bearing — diverse processing nodes are what sustained complexity requires, which is why totalitarian monocultures self-destruct.

MacAskill's Better Futures operates in the gap between these two ontologies. He built a telescope that sees the right things. He's using a lens ground from the wrong ontology.

VII. The Fork

Call the alternative the mechanist ontology. The core commitment: mechanisms are real, intentions are not. What actually produces outcomes is the causal architecture (selection pressure, replicator dynamics, institutional design), not the stated purpose (values, democracy, moral theories). Study what systems do, not what they say.

The fork between the rationalist tradition and mechanist ontology is not a disagreement about reasoning quality. Rationalists reason well. The fork is about what the reasoning is applied to.

Rationalists optimize beliefs — is this belief well-calibrated? Mechanists optimize the territory — what does this mechanism actually produce? Rationalists ask whether the formalization is internally consistent. Mechanists ask whether the formalization corresponds to an actual physical process. Rationalists build elaborate deductive structures on axioms they trust. Mechanists check whether the axioms correspond to mechanisms before building anything.

The individualist axiom is where the fork bites hardest. Rationalists inherited it from Bentham through Sidgwick through Singer. They never checked it against physical reality. They built an extraordinary deductive apparatus on top of it — expected value theory, population ethics, cause prioritization frameworks, the entire EA infrastructure. The apparatus is internally consistent. It may not correspond to how civilizations actually work.

The last step is not a change in reasoning quality. It is a change in foundation. From "we don't know what's valuable, so preserve options" to "physics constrains which configurations persist, and the constraints are discoverable." From a hedge to a ground truth. From moral uncertainty to structural analysis.

This framework does make one normative commitment: more aliveness — sustained syntropy — is preferable to less. That's an axiological wager, not a derivation. But it is one commitment, stated explicitly. MacAskill's moral uncertainty also contains a normative commitment — "preserving options is better than not preserving them" — but it is hidden, smuggled in as methodology rather than stated as axiom. His viatopia already presupposes that persistence and diversity matter. He just doesn't ground it.

MacAskill built the telescope. The last step is to trust what it shows.

The physics: The Question Nobody Asks → Flourishing Is Maximum Safety Margin.

Related reading:

• The Question Nobody Asks — the question MacAskill doesn't ask, and its derivation
• Flourishing Is Maximum Safety Margin — why MacAskill's S and F are the same variable
• Hume Was Right — why physics-grounded constraints don't cross the is-ought gap
• The Original Sin of History — the Bentham-to-paperclip genealogy MacAskill inherits
• There Is No Altruism — what happens to EA's foundational concept under mechanist ontology
• Values Aren't Subjective — the category error that enables the hedge
• Values Are Replicators — why moral theories are not independent discoveries about reality
• The Mechanist Tradition — the 2,300-year genealogy behind the mechanist ontology