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def definition def or abbrev high

sigmaCost

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SigmaCost assigns a real-valued agency imbalance to each trolley choice, returning 1 for the active pull and 0 for do-nothing. Decision theorists resolving Newcomb-style paradoxes under sigma conservation cite it to quantify the J-sigma tradeoff in the classic dilemma. The definition is realized by exhaustive case analysis on the two constructors of TrolleyChoice.

claimFor a trolley choice $c$, the sigma-cost is defined by $1$ when $c$ is the pull action and $0$ when $c$ is the do-nothing action.

background

TrolleyChoice is the inductive type with constructors pull and doNothing, representing the active intervention versus passive option in the runaway-trolley scenario. Sigma-cost measures the agency imbalance created by a choice, directly analogous to the NewcombParadox.sigmaCost definition that assigns 0 to one-boxing and 1 to two-boxing. Upstream cost functions from MultiplicativeRecognizerL4.cost and ObserverForcing.cost supply the general recognition-cost machinery that this definition specializes to the trolley setting. The module frames the trolley problem as a strict J-sigma tradeoff: pulling reduces lives lost but introduces sigma-skew, while doing nothing preserves sigma at the cost of higher J.

proof idea

The definition is a direct pattern match on the TrolleyChoice constructors, returning the constant 1 for pull and 0 for doNothing.

why it matters in Recognition Science

This definition supplies the sigmaCost field required by TrolleyTradeoffCert and is referenced by NewcombResolutionCert, oneBox_dominates_under_sigma_conservation, and related results to establish dominance under sigma conservation. It fills the philosophical-paradoxes row of the Recognition Science framework by quantifying the J-sigma tradeoff, where active killing breaks the no-action equilibrium even while lowering J-cost. The construction connects to the eight-tick octave and RCL through the sigma-conservation enforced by R-hat action.

scope and limits

formal statement (Lean)

  73def sigmaCost (c : TrolleyChoice) : ℝ :=

proof body

Definition body.

  74  match c with
  75  | TrolleyChoice.pull      => 1
  76  | TrolleyChoice.doNothing => 0
  77
  78/-- J-cost proxy: lives lost as real number. -/

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depends on (5)

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