One important result of our habit of thus forcing the universe to become "the bond-slave of human thought" is to be found, as Bacon notes, in our proneness to "suppose the existence of more order and regularity in the world" than is actually to be discovered there. While we read design and purpose into the phenomena of Nature because we are conscious of design and purpose in our own activities, thus allowing ourselves to drift into the metaphysical doctrine of Final Causes, we also do our best to bring Nature's multitudinous operations into such definite formulas as will satisfy our love of plan and symmetry. We are not content till we can systematize and digest, whence our continual recourse to loose analogies and fanciful resemblances. We start from an imagined necessity of order, or from some conception of things attractive because of its apparent simplicity, and then reason out from this into the facts of Nature. Mill furnishes some telling examples. "As late as the Copernican controversy it was urged, as an argument in favor of the true theory of the solar system, that it placed the fire, the noblest element, in the center of the universe. This was a remnant of the notion that the order of the universe must be perfect, and that perfection consisted in conformity to rules of procedure, either real or conventional. Again, reverting to numbers, certain numbers were _perfect_, therefore these numbers must obtain in the great phenomena of Nature. Six was a perfect number--that is, equal to the sum of all its factors--an additional reason why there must be exactly six planets. The Pythagoreans, on the other hand, attributed perfection to the number ten, but agreed in thinking that the perfect numbers must be somehow realized in the heavens; and knowing only of nine heavenly bodies to make up the enumeration, they asserted 'that there was an _antichthon_, or counter-earth, on the other side of the sun, invisible to us.' Even Huygens was persuaded that when the number of heavenly bodies had reached twelve it could not admit of any further increase. Creative power could not go beyond that sacred number."[20] Do these concrete illustrations of perverse reasoning strike us as ludicrous? It is because they are taken from an order of ideas long since outgrown. The tendencies they exemplify have not been outgrown. We have only to keep a vigilant eye on our own mental conduct to be convinced that we are very apt to begin with some general notion of "the fitness of things," or what "ought to be," and to argue thence to conclusions not a whit less absurd essentially than those just referred to. [Footnote 20: Logic, ninth edition, Book V, chapter v, § 6.]