# Naturalistic fallacy > The logical error of claiming that something is “morally right” solely because it “exists in nature.” The moralistic fallacy is its converse. The logical error of claiming that something is "morally right" solely because it "exists in nature." The [moralistic fallacy](https://wiki.g15e.com/pages/Moralistic%20fallacy.txt) is its converse. More generally, the error of claiming that something is "right" or "good" solely on the basis of the fact that something "exists." See . ## Examples " does not exist in nature. Therefore, homosexuality is a sin." - This is a naturalistic fallacy because it derives the normative claim "homosexuality is wrong" solely from the factual claim "homosexuality does not exist in nature." - Since homosexuality is commonly observed in various species in nature, "homosexuality does not exist in nature" is a *false factual statement*. A "factual statement" means a statement **about facts**, which may be true or false, rather than a statement **that is true**. The important point is that deriving an ought solely from factual statements is a naturalistic fallacy whether those statements are true or false. In other words, the claim above is wrong regardless of whether homosexuality actually exists in nature, rather than being wrong because it does exist. Claims of the form "humans evolved in such-and-such a way, so modern humans should eat accordingly to be healthy" (see [Dietary suggestions based on human evolutionary history](https://wiki.g15e.com/en/pages/Dietary%20suggestions%20based%20on%20human%20evolutionary%20history.txt)): - The claim that humans evolved in a particular way during the Paleolithic, so eating in accordance with that way is healthy. - But [evolutionary adaptation](https://wiki.g15e.com/en/pages/Evolutionary%20adaptation.txt) is geared toward reproduction and the minimum survival needed for it, rather than long-term human well-being. Paleolithic dietary patterns were optimized only to let humans live reasonably well until about age 50, provided they did not die of other causes. For comparison, human in modern industrialized societies exceeds 80 years. ## Misconceptions ### The misconception that including any factual statement among the premises makes an argument fallacious argues in [Ethics for Animals](https://wiki.g15e.com/en/pages/%EB%8F%99%EB%AC%BC%EC%9D%84%20%EC%9C%84%ED%95%9C%20%EC%9C%A4%EB%A6%AC%ED%95%99.txt): > Attempts to derive norms from facts are very common. Even [utilitarianism](https://wiki.g15e.com/en/pages/Utilitarianism.txt), which seeks moral right and wrong in what promotes pleasure or pain, does not escape the naturalistic fallacy. … Whatever conclusion we reach about the moral status of animals, the moment we use the or , we commit the naturalistic fallacy. This claim rests on a mistaken understanding of the naturalistic fallacy. Deriving a value statement from premises that include factual statements is not, in itself, fallacious. The naturalistic fallacy is deriving a value statement when the premises contain **only** factual statements. For utilitarianism to commit the naturalistic fallacy in the way Choi Hoon claims, its argument would have to be as follows: - **Premise**: An individual has an interest in pursuing pleasure and avoiding pain. - **Conclusion**: That individual's interests should receive equal consideration. This argument is fallacious because its conclusion, a value statement, is derived from premises containing only factual statements. But the actual utilitarian argument is as follows: - **Premise 1**: An individual has an interest in pursuing pleasure and avoiding pain. (Why classical utilitarianism is "hedonistic" utilitarianism.) - **Premise 2**: If an individual has interests, that individual's interests should receive equal consideration. (Utilitarianism's [principle of equal consideration](https://wiki.g15e.com/en/pages/Principle%20of%20equal%20consideration.txt).) - **Conclusion**: The interests of individuals capable of experiencing pleasure and pain should receive equal consideration. (The conclusion logically derived from those premises.) In this argument, premise 1 is a factual statement ("is"), but premise 2 is a value statement ("ought"). Since the value statement in the conclusion is not derived "solely from factual statements," this is not a naturalistic fallacy. Choi Hoon goes on to try to "rescue" the argument for animal rights from the naturalistic fallacy. But it never committed the fallacy in the first place, so there is nothing to rescue. ### The misconception that a fallacy requires a "false factual statement" among the premises The naturalistic fallacy is not fallacious because the factual statements in its premises are "false." Regardless of whether the factual statements in the premises are true or false, deriving a value statement solely from factual statements is fallacious. There is therefore no need to determine whether the statements in the premises are true in order to judge whether an argument commits the naturalistic fallacy. ## See also -