One of the most famous parts of Bacon’s philosophy is his enumeration of what he calls ‘idols’, by which he means bad habits of mind that cause people to fall into error. Of these he enumerates four kinds. ‘Idols of the tribe’ are those that are inherent in human nature; he mentions in particular the habit of expecting more order in natural phenomena than is actually to be found. ‘Idols of the cave’ are personal prejudices, characteristic of the particular investigator. ‘Idols of the market-place’ are those that have to do with the tyranny of words. ‘Idols of the theatre’ are those that have to do with received systems of thought; of these, naturally, Aristotle and the scholastics afforded him the most noteworthy instances.

Bertrand Russell, History of Western Philosop…, loc. 1999