pith. sign in
def

derivedCost

definition
show as:
module
IndisputableMonolith.Foundation.LogicAsFunctionalEquation
domain
Foundation
line
69 · github
papers citing
7 papers (below)

plain-language theorem explainer

derivedCost extracts the single-variable cost function F(r) = C(r, 1) from any comparison operator C on positive reals. Researchers deriving the Recognition Composition Law or the continuous-combiner classification cite it when reducing two-argument comparisons to a scale-invariant cost on ratios. The definition is a direct projection that fixes the second argument at the multiplicative identity.

Claim. Let $C : (0,∞) × (0,∞) → ℝ$ be a comparison operator. The derived cost is the function $F : (0,∞) → ℝ$ defined by $F(r) := C(r, 1)$.

background

ComparisonOperator is the type of maps from pairs of positive reals to reals that return the cost of comparing two quantities. The module encodes the four Aristotelian constraints (identity, non-contradiction, excluded middle, composition consistency) as structural properties on such operators. Under scale invariance the derived cost is well-defined on the multiplicative group of positive ratios.

proof idea

The definition is a one-line projection: derivedCost C is the function sending r to C r 1. No lemmas or tactics are invoked; the body is the direct extraction of the cost by fixing the second argument at 1.

why it matters

This definition supplies the cost function F that appears in generatorOfLawsOfLogic to extract a non-trivial generator from SatisfiesLawsOfLogic. It is the input to the continuous-combiner theorems in GeneralizedDAlembert (bilinear classification, log-smoothness bootstrap, finite-smoothness promotion). In the Recognition framework it converts the Aristotelian laws into the functional equation whose solution yields the J-cost and the phi-ladder.

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