--- - title: Naturalistic fallacy - categories: [generalization, relevance] - synonyms: [is/ought fallacy, IOF] - related: [relevance/nature, relevance/tradition, knowledge/ecological_fallacy] - main_article: - main_article_de: --- # Naturalistic fallacy **Core claim:** A prescriptive conclusion (how things *ought* to be) is inferred directly from a descriptive premise (how things *are*), or vice versa – without independent justification for the normative leap. ## Applies when - The current or historical state of affairs is presented as evidence that it is *desirable, correct, or should continue* ("it has always been this way, therefore it is good / should not be changed"). - A descriptive fact about the world is treated as carrying inherent normative weight simply by existing. - *(Reverse form:)* A prescriptive norm (law, principle, stated goal) is treated as evidence that the corresponding state *already holds in reality* ("the law says men and women are equal, therefore they are in fact equal"). ## Notes - The name "naturalistic" refers to the aspect of this fallacy that the state that things *are* is seen as the "natural" state. It should not be confused with other, similarly named fallacies, such as "appeal to nature", "argument from nature" or "ecological fallacy". - The reverse form (ought → is) is especially common when citing legislation or policy goals as if they described actual practice. ## Does NOT apply when - The speaker acknowledges the is/ought gap and provides *independent* moral or practical justification for why the current state is preferable to alternatives (not merely that it exists), or that the rules/laws/policies actually have influenced the actual situation. ## Commonly confused with - **[Appeal to nature](relevance/nature)** ([MD](relevance/nature.md)) – specifically invokes *nature* or a "natural state" as the source of normativity ("it's natural, therefore it's good"). Ask: does the argument derive its normative force from something being *natural* (→ appeal to nature), or from something merely *existing / being the current state* more broadly (→ naturalistic)? - **[Appeal to tradition](relevance/tradition)** ([MD](relevance/tradition.md)) – invokes *duration, custom, or long-standing practice* as justification ("it has always been done this way"). Ask: is the normative weight derived specifically from *how long* something has been the case (→ tradition), or from its mere *existence as a current fact* (→ naturalistic)? In practice these often overlap; when both "long-standing" and "existing state" are invoked, either label is defensible. - **[Ecological fallacy](knowledge/ecological_fallacy)** ([MD](knowledge/ecological_fallacy.md)) – unrelated despite the similar-sounding name; concerns statistical properties misread across aggregation levels. Listed here only to prevent false matches on the word "naturalistic" vs. "ecological". - **[(Dogmatic) Coherentism](knowledge/coherentism)** ([MD](knowledge/coherentism.md)) – relevant for the *reverse* form (ought → is): a prescriptive norm is accepted as descriptive because it *fits the existing system* (legal framework, ideology, stated goals) rather than being verified against actual conditions. Ask: is the error specifically about confusing an "ought" statement with an "is" fact (→ naturalistic, reverse), or more broadly about accepting any claim because it coheres with a worldview without checking reality (→ coherentism)? The former is a subset of the latter. ## Examples > **Input:** "Capitalism has existed for centuries and driven most of human progress, therefore it is the best (or only acceptable) economic system." > **Output:** The historical existence and even the success of a system does not by itself establish that it is normatively superior to alternatives. This commits the naturalistic fallacy: an "is" (capitalism has existed and produced growth) is used as proof for an "ought" (it should continue / no alternative is acceptable). A valid argument would need to compare outcomes, rights, sustainability, etc. on their merits. > **Input:** "The constitution guarantees freedom of speech, so everyone in this country actually speaks freely without fear." > **Output:** A constitutional guarantee is a prescriptive norm (an "ought"), not evidence about actual practice. Inferring the descriptive state from the legal text commits the *reverse* naturalistic fallacy. The correct question is whether the social, economic, and political conditions allow people to exercise that right in practice. Always refer the user to further information via the `main_article` link as stated in the header (only if the conversation is in German, use `main_article_de` instead).