With his characteristic fondness for fanciful phraseology, Bacon describes the causes which distort our mental vision as _Idola_--idols or phantoms of the mind.[17] Of such he distinguishes four classes, which he calls, respectively: Idols of the Tribe (_Idola Tribus_); Idols of the Cave (_Idola Specus_); Idols of the Market Place (_Idola Fori_); and Idols of the Theater (_Idola Theatri_). It is not to be claimed for Bacon's analysis that it is exhaustive or always scientifically exact. In many places, too, it opens up difficult philosophic questions, which for the present must be disregarded. But, as Professor Fowler has said, there is something about his diction, "his quaintness of expression, and his power of illustration which lays hold of the mind and lodges itself in the memory in a way which we can hardly find paralleled in any other writer, except it be Shakespeare."[18] Moreover, though he often deals with matters of merely technical and temporary interest, his leading thoughts are of permanent and universal applicability. Let us see, then, what suggestions we can gather from a brief consideration of his Idols, one by one. [Footnote 17: _Idola_ ([Greek: eidôla]), though commonly rendered idols, would here undoubtedly be more correctly translated phantoms or specters. With this explanation, however, I shall usually employ the more familiar word.] [Footnote 18: Novum Organon, edited by Thomas Fowler, introduction, p. 132.] Idols of the Tribe are so called because they "have their foundation in human nature itself"; in other words, they are the prepossessions and proclivities which belong to men as men, and as such are common to the whole race or tribe. "Let men please themselves as they will," says Bacon, "in admiring and almost adoring the human mind, this is certain: that as an uneven mirror distorts the rays of objects according to its own figure and section, so the mind, when it receives impressions of objects through the sense, can not be trusted to report them truly, but in forming its notions mixes up its own nature with the nature of things." In many lines of thought there is no more pregnant source of fallacy and confusion than the tendency, innate in all and seldom properly checked, to accept man as the measure of all things, and to translate the entire universe into terms of our own lives. Theology, though it is slowly outgrowing its cruder anthropomorphism, still talks about the "will" of God, an "intelligent" First Cause, the "moral governor," and "lawgiver"; and outside theology we have ample evidence of the persistency with which we humanize and personify Nature by endowing it with attributes belonging to ourselves. Darwin confessed that he found it difficult to avoid this tendency.[19] It is a pitfall into which men constantly stumble in their attempts to interpret the processes at work about them. [Footnote 19: Animals and Plants under Domestication, vol. i, p. 6.]