Book 2 — 122.
J. M. (John McFarland) Kennedy translation
The Purposes in Nature.—Any impartial investigator who examines the history of the eye and its form in the lower creatures, and sees how the visual organ was slowly developed, cannot help recognising that sight was not the first purpose of the eye, but probably only asserted itself when pure hazard had contributed to bring together the apparatus. One single example of this kind, and the “final purposes” fall from our eyes like scales.