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Naturalistic Fallacy

The metaethical error of identifying goodness with a natural property, exposed by the open-question argument — for any proposed good = N, 'but is N good?' stays a meaningful question, so goodness cannot be identical with any natural property it merely co-occurs with.

Core Idea

The naturalistic fallacy, from G. E. Moore, is the metaethical error of identifying the normative property goodness with a natural or descriptive property — the pleasant, the desired, the evolutionarily fit — so the normative question seems settled once the facts are. Moore's open-question argument is the diagnostic: for any proposed good = N, "but is N good?" remains meaningful and non-trivial, which it would not be if the identification were definitional. It is distinct from Hume's inferential is-ought gap and the rhetorical appeal to nature.

Scope of Application

Bounded to arguments that read a value off a fact, across the philosophical subfields adjudicating description-to-norm crossings.

  • Metaethics — the home: the open-question battleground behind non-naturalism and Cornell realism.
  • Philosophy of biology — against sociobiology and "human-nature" arguments.
  • Bioethics — defusing "playing God" and "unnatural therefore wrong" objections.
  • Public-health discourse — auditing "natural" foods and lifestyle appeals.
  • Law and environmental ethics — natural-law arguments and pristine-baseline conservation claims.

Clarity

Naming the fallacy makes legible a missing premise that appeals to the natural, normal, or evolved keep invisible, exposing the is-to-ought step as logically incomplete and telling the analyst to demand the connecting principle. Its subtler service forestalls an overcorrection: facts cannot settle a normative question, but they are typically necessary to one, merely never sufficient. Holding "necessary" apart from "sufficient" keeps the fallacy from curdling into a blanket dismissal of empirically informed ethics.

Manages Complexity

A heterogeneous list of value-off-fact appeals collapses under one portable test — the open question — that settles every candidate N at a stroke, reading the verdict off the openness of the question rather than the merits of the particular N. Localizing the defect to a missing normative premise fixes a clean branch structure: semantic equating (Moore), inferential is-ought gap (Hume), bare appeal to nature (rhetorical), and complete argument (no fallacy).

Abstract Reasoning

The fallacy licenses a diagnostic move (run the open-question test; discriminate which of three confusions is in play), an interventionist move (probe for the unstated ought, or construct natural-but-bad / unnatural-but-good counterexamples), a boundary-drawing move (guard against the overcorrection that facts are irrelevant; rule a complete argument no fallacy), and order-of-events reconstruction discipline (separate the premises and check whether the ought was stated or hidden).

Knowledge Transfer

Within ethics and its applied branches the fallacy transfers as mechanism — the open-question test and necessary-versus-sufficient guard run unchanged, though what usually travels is the diagnostic discipline, and the applied cases are often the Humean or appeal-to-nature sibling under Moore's name. Beyond ethics the portable core is the fact-value distinction itself, carried by the parent normativity / fact_value_distinction; Moore's semantic property-non-identity claim is home-bound philosophical furniture.

Relationships to Other Abstractions

Local relationship map for Naturalistic FallacyParents appear above the current abstraction, mutual partners to the right, and children below. Node labels state whether each abstraction is prime or domain-specific; colors identify relation types.Naturalistic FallacyDOMAINPrime abstraction: Normativity — is part ofNormativityPRIME

Current abstraction Naturalistic Fallacy Domain-specific

Parents (1) — more general patterns this builds on

  • Naturalistic Fallacy is part of Normativity Prime

    Moore's Naturalistic Fallacy internally contains a normative property, goodness, that is illicitly identified with a descriptive property.

Hierarchy path (1) — routes to 1 parentless root

Neighborhood in Abstraction Space

Naturalistic Fallacy sits in a crowded region of the domain-specific corpus (24th percentile for distinctiveness): several abstractions share nearly its structure, so a description that fits it tends to fit its neighbors too.

Family — Unclustered & Miscellaneous (309 abstractions)

Nearest neighbors

Computed from structural-signature embeddings · 2026-07-12