Argument from Natural Source

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© 2011-2019 by Zack Smith. All rights reserved.

Argument from Natural Source

This is also called Appeal to Nature, Argumentum ad naturam or the Naturalistic Fallacy.

Argument from Natural Source is the claim that because a thing is natural, a secondary claim is true, typically one stating that the thing is therefore somehow good or beneficial.

  • Some Object A has a natural origin.
  • Therefore some Proposition P is true e.g. that A is good. ]]

The secondary claim can really be anything, i.e. that Object A is good, or bad, or purple, or anything else.

An inverse form of this fallacy is to say that because something is unnatural, a secondary claim is true.

This fallacy is often deployed in product marketing materials, or by consumers who are enthusiastic about products.


This tobacco is grown organically, therefore it is good for you.

Every banana contains a certain amount of naturally-occurring radioactive isotopes, but it's natural therefore you need not worry about it.

In the early days of petroleum extraction, a cure-all called Seneca Oil or Rock Oil that was largely petroleum was sold by a number of traveling con men, including John D. Rockefeller's father William. In the case of Kier's Genuine Petroleum or Rock Oil<i> the bottle touted it as A Natural Remedy.

Inverse example: In the early days of plastic manufacture, man-made products were so popular than some considered them better than natural products. Cellophane was a wonder of industry.


Naturalness itself does not prove goodness, since many natural things are unhealthy, dangerous, or deadly. A snake bite is 100% natural, as is uranium.

Naturalness is used as a distraction for the arguer's not having supporting evidence for his secondary claim of goodness or good effect. You merely need to ask for that evidence.

The naturalness of a thing may itself be a lie, especially if it is a food product. While debunking the fallacy doesn't really require it, you could examine such claims of naturalness.

In nature, a poison and a medicine may exist in the same plant, or may exist in the same part of a plant at different times of year.


The Naturalistic Fallacy also refers to the is-ought problem of deciding what ought to be based on what is. Making prescriptive statements from observations i.e. descriptive statements is a tricky problem that is often fouled up, as in the case of Social Darwinism.