Idols of the Cave

Idola specus (singular Idolum specus), normally translated as "Idols of the Cave" (or "Idols of the Den"), is a type of logical fallacy whereby the peculiar biases of individuals lead them to errors. This Latin term was coined by Sir Francis Bacon and used in his Novum Organum, one of the earliest treatises arguing the case for the logic and method of modern science. He described them as deriving from "the peculiar constitution, mental or bodily, of each individual; and also in education, habit, and accident".

The idola specus are prejudices, by which individuals inappropriately extend norms or tenets that derive his or her own culture and social group, or to his or her own preferences. Racism, sexism and, more generally just "biases" are examples of idola specus, but the concept goes beyond them to the criticism of all forms of irreflexive subjectivity or individual predisposition.

The term is one of four such "idols" which represent "idols and false notions which are now in possession of the human understanding, and have taken deep root therein, not only so beset men's minds that truth can hardly find entrance, but even after entrance is obtained, they will again in the very instauration of the sciences meet and trouble us, unless men being forewarned of the danger fortify themselves as far as may be against their assaults".

Besides idola specus, there are also idola tribus (Idols of the Tribe, caused by human nature), idola fori, (Idols of the Market Place, caused by language) and idola theatri (Idols of the Theatre, which are caused by the influence of philosophers).

The Idols of the Cave are the idols of the individual man. For everyone (besides the errors common to human nature in general) has a cave or den of his own, which refracts and discolors the light of nature, owing either to his own proper and peculiar nature; or to his education and conversation with others; or to the reading of books, and the authority of those whom he esteems and admires; or to the differences of impressions, accordingly as they take place in a mind preoccupied and predisposed or in a mind indifferent and settled; or the like. So that the spirit of man (according as it is meted out to different individuals) is in fact a thing variable and full of perturbation, and governed as it were by chance. Whence it was well observed by Heraclitus that men look for sciences in their own lesser worlds, and not in the greater or common world.

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