The Epistemic Boundary Theorem: Completing Hayek's Knowledge Argument for System Welfare

WTI crude prices aggregate oil-trade knowledge while atmospheric welfare stays invisible

The paper starts with West Texas Intermediate crude oil because it shows the whole theorem in one case: the same price can process dispersed supply-and-demand knowledge and carry no signal about CO₂ persistence, ocean acidification, extreme weather, or unborn populations.

• Included in the price: Permian Basin geology, Strait of Hormuz tanker schedules, Rotterdam refinery maintenance, New England heating demand, Singapore speculation
• Excluded from the price: welfare costs imposed on non-parties, including populations not yet born
• The exclusion is structural because atmospheric welfare cannot enter the buyer-seller transaction as current willingness-to-pay

Prices aggregate knowledge if and only if it can enter bilateral willingness-to-pay

The HEBT completes Hayek's 1945 knowledge argument by adding the missing negative half: prices coordinate bilateral knowledge with high power, but they do not aggregate non-bilateral welfare knowledge at all.

• Bilateral knowledge includes willingness-to-pay, willingness-to-sell, time preferences, risk assessments, and expectations about future trades
• W_C includes commons welfare, future generations, epistemic infrastructure, and non-priced environmental stocks
• The theorem is framed as a domain boundary, not as a claim that markets are slow, distorted, or poorly designed

Hayek deepened the bilateral knowledge argument across four phases

The paper reads Hayek's career as a six-decade development of one question: how decentralized mechanisms process information. Each phase strengthens the bilateral result without formalizing where it stops.

• 1929-1941: interest rates coordinate time preferences and production opportunities, while malinvestment costs spill beyond borrowers and lenders
• 1935-1948: the socialist calculation debate shows prices communicate dispersed, tacit knowledge better than a planning board
• 1944-1979: spontaneous order extends the knowledge argument to legal, cultural, and political institutions
• 1968-1988: competition discovers new products, methods, and opportunities, but only when they can become profitable exchanges

Hayek recognized four welfare classes that his formal price theory did not price

The paper names four classes in Hayek's corpus that matter for welfare yet sit outside the information set processed by bilateral prices.

• S₁ epistemic commons: property rights, contract enforcement, monetary stability, and rules of just conduct
• S₂ spontaneous order: cooperation, trust, institutional coherence, and systemic resilience
• S_2a future generations: people who cannot express willingness-to-pay in current markets
• S₃ non-priced commons: atmospheric composition, oceanic pH, biodiversity, hydrological cycles, topsoil depth, and aquifer levels

The socialist calculation debate made the boundary result hard for Hayek to state

The paper argues that Hayek had the tools to see the boundary, but his debate context and intellectual commitments made formalizing it costly.

• Against Lange's market-socialist planning board, Hayek only needed to prove that prices beat central collection inside bilateral coordination
• After The Road to Serfdom, stating structural limits of prices would have looked like a concession to interventionism
• Welfare economics was Pigouvian territory, and Hayek's project was built against that framework
• Coase redirected externality theory toward bargaining, but atmosphere and future generations do not fit the zero-transaction-cost bilateral case

The theorem separates bilateral transaction knowledge from system welfare knowledge

The model assigns a precise domain to the price system. K(T) is the knowledge that can be expressed through bilateral transactions; K(W_C) is welfare-relevant knowledge that cannot be expressed that way.

• A1: prices aggregate bilateral knowledge
• A2: bilateral knowledge is a proper subset of all welfare-relevant knowledge
• A3: system welfare knowledge is not expressible as bilateral willingness-to-pay
• Examples of K(W_C): atmospheric CO₂, antibiotic resistance prevalence, aquifer depletion, biodiversity loss

The price system has no aggregation signal for W_C

A1 gives the affirmative Hayek result inside K(T). A2 and A3 give the boundary: K(W_C) does not enter the transaction knowledge set, so prices cannot aggregate it.

• Domain Identity Corollary: the epistemic domain of prices is identical to the Missing System Theorem's bilateral payoff space
• Discovery Failure Corollary: competition discovers opportunities inside the bilateral transaction space, not welfare effects outside it
• Hayek's claims remain valid as special cases restricted to bilateral knowledge

This is not the usual Pigouvian market-failure story

A market failure story says the price should include an external cost but does not. The HEBT says the price mechanism has no internal way to generate the missing welfare knowledge in the first place.

• An optical telescope analogy makes the distinction: failing to detect radio waves is a domain limit, not poor optical performance
• A carbon tax works only after climate science estimates the external welfare cost
• Cap-and-trade works only after an externally set cap defines the constraint that markets then allocate around

Hayek is right inside bilateral payoffs and Pigou is right outside them

The paper resolves the Austrian-Pigouvian conflict by assigning each tradition to a different region of welfare space.

• Hayek: prices process dispersed, tacit, bilateral knowledge better than central planning
• Pigou: welfare consequences can exist outside private transactions and require corrective instruments
• Coase applies within the bargaining domain; atmosphere, unborn people, and planetary stocks lack the needed counterparties
• Bilateral exchange can coordinate efficiently while system welfare deteriorates

HEBT and MST find the same boundary from information and value theory

The HEBT is the information-theoretic companion to the Missing System Theorem. The MST says bilateral payoffs cannot span full welfare when W_C is external; the HEBT says prices cannot aggregate knowledge about that same excluded welfare.

• MST result: bilateral mechanisms are value-optimal within their payoff space and incomplete beyond it
• HEBT result: bilateral prices are information-optimal within their knowledge space and blind beyond it
• Together they define one boundary from two directions: what bilateral mechanisms can value and what they can know

The paper links the boundary to $73.8T in annual excluded welfare

The formal result is Tier 2 theory with conceptual calibration. The empirical counterpart comes from the Reform Dividend estimate across the SAPM research program.

• $73.8T per year is reported as the aggregate welfare cost of epistemic exclusion
• The estimate spans 61 domains
• Each domain is calibrated with Monte Carlo simulation using 100,000 draws, seed = 42, and 3+ distribution types per domain
• Named domains include PFAS molecular persistence, nuclear waste decay, firearms public safety costs, and factory farming animal welfare

Measure W_C outside prices, then translate it into bilateral incentives

The paper's policy answer is Hayekian in structure: do not replace decentralized allocation with central planning. Build external knowledge institutions for W_C, then use Pigouvian instruments to transmit those outputs into prices.

• Monitoring institutions generate facts prices cannot discover, such as emissions, persistence, depletion, prevalence, or resilience loss
• Assessment institutions convert those facts into welfare-relevant measures
• Reporting institutions make the measures usable for taxes, caps, standards, disclosure, or liability
• Prices then allocate within the translated constraint using their bilateral coordination strength