Appeal to nature
General form of this type of argument:
- N is natural.
- Therefore, N is good or right.
- U is unnatural.
- Therefore, U is bad or wrong.
Julian Baggini explains that "[E]ven if we can agree that some things are natural and some are not, what follows from this? The answer is: nothing. There is no factual reason to suppose that what is natural is good (or at least better) and what is unnatural is bad (or at least worse)."
In some contexts, the use of the terms of "nature" and "natural" can be vague, leading to unintended associations with other concepts. The word "natural" can also be a loaded term — much like the word "normal", in some contexts, it can carry an implicit value judgement. An appeal to nature would thus beg the question, because the conclusion is entailed by the premise.
Opinions differ regarding appeal to nature in rational argument. Sometimes, it can be taken as a rule of thumb that admits some exceptions, but nonetheless proves to be of use in one or more specific topics, (or in general). As a rule of thumb, natural or unnatural facts provide presumptively reliable good or bad values, barring evidence to the contrary. Failure to consider such evidence commits a fallacy of accident under this view.
The meaning and importance of various understandings and concepts of "nature" has been a persistent topic of discussion historically in both science and philosophy. In Ancient Greece, “the laws of nature were regarded not [simply] as generalized descriptions of what actually happens in the natural world… but rather as norms that people ought to follow… Thus the appeal to nature tended to mean an appeal to the nature of man treated as a source for norms of conduct. To Greeks this… represented a conscious probing and exploration into an area wherein, according to their whole tradition of thought, lay the true source for norms of conduct.”
In modern times, philosophers have challenged the notion that human beings' status as natural beings should determine or dictate their normative being. For example, Rousseau famously suggested that "We do not know what our nature permits us to be." More recently, Nikolas Kompridis has applied Rousseau's axiom to debates about genetic intervention (or other kinds of intervention) into the biological basis of human life, writing:
[T]here is a domain of human freedom not dictated by our biological nature, but [this] is somewhat unnerving because it leaves uncomfortably open what kind of beings human beings could become… Put another way: What are we prepared to permit our nature to be? And on what basis should we give our permission?
Kompridis writes that the naturalistic view of living things, articulated by one scientist as that of "machines whose components are biochemicals" (Rodney Brooks), threatens to make a single normative understanding of human being the only possible understanding. He writes, "When we regard ourselves as 'machines whose components are biochemicals,' we not only presume to know what our nature permits us to be, but also that this knowledge permits us to answer the question of what is to become of us… This is not a question we were meant to answer, but, rather, a question to which we must remain answerable."
Some popular examples of the appeal to nature can be found on labels and advertisements for food, clothing, and alternative herbal remedies. Labels may use the phrase "all-natural", to imply that products are environmentally friendly and/or safe. However, many toxic substances are found in nature, including in common plant sources and herbs such as hemlock, nightshade, belladonna, and poisonous mushrooms, and these may have serious side effects.
See also 
- Moore, George E.: Principia Ethica, Barnes and Noble Publishing, Inc (1903, 2005) p. 47
- Curtis, Gary N. (15 November 2010). "Fallacy Files — Appeal to Nature". fallacyfiles.org. Retrieved 13 February 2011.
- Baggini, Julian (2004). Making sense: philosophy behind the headlines. Oxford University Press. pp. 181–182. ISBN 978-0-19-280506-5.
- Groarke, Leo (2008). Fallacy Theory. In Zalta, Edward N. "Informal Logic". Stanford Encyclopedia of Philosophy (Fall 2008 ed.). "Informal logic is sometimes presented as a theoretical alternative to formal logic. This kind of characterization may reflect early battles in philosophy departments which debated, sometimes with acrimony, whether informal logic should be considered "real" logic. Today, informal logic enjoys a more conciliatory relationship with formal logic. Its attempt to understand informal reasoning is usually (but not always) couched in natural language, but research in informal logic sometimes employs formal methods and it remains an open question whether the accounts of argument in which informal logic specializes can in principle be formalized."
- Saunders, Jason Lewis (26 October 2008). "Western Philosophical Schools and Doctrines: Ancient and Medieval Schools: Sophists: Particular Doctrines: Theoretical issues.". Encyclopaedia Britannica. Retrieved 07 February 2011.
- Jean-Jacques Rousseau, Emile: or, On education, USA: Basic Books, 1979, p. 62.
- “The current scientific view of living things is that they are machines whose components are biochemicals.” Rodney Brooks, "The relationship between matter and life", Nature 409 (2010), p. 410.
- Nikolas Kompridis, "Technology's Challenge to Democracy: What of the Human?", Parrhesia Number 8 (2009), pp. 23–31.
- Flew, Antony (1998). How to Think Straight: An Introduction to Critical Reasoning. Prometheus Books. ISBN 978-1-57392-239-5.
- Nature, Human Nature, and Biotechnology
- Appeal to Nature
- Dietary Supplements: How To Know What Is Safe American Cancer Society: §The "Natural Is Safe" or "Natural Is Better" Myth (Archived from the original 18 April 2008)