In this argument there are three very palpable fallacies: the first is the rough application of measurement to the heads, necks, and limbs, without observing the subtile differences of proportion and position of parts in the members themselves, for it would be strange if the different adjustment of the ears and brow in the dog and horse, did not require a harmonizing difference of adjustment in the head and neck. The second fallacy is that above specified, the supposition that proportion cannot be beautiful if susceptible of variation, whereas the whole meaning of the term has reference to the adjustment and functional correspondence of infinitely variable quantities. And the third error is the oversight of the very important fact, that, although "different and even contrary forms and dispositions are consistent with beauty," they are by no means consistent with equal _degrees_ of beauty, so that, while we find in all the presence of such proportion and harmony of form, as gifts them with positive agreeableness consistent with the station and dignity of each, we perceive, also, such superiority of proportion in some (as the horse, eagle, lion, and man for instance) as may best be in harmony with the nobler functions and more exalted powers of the animals. Sec. 15. Constructive proportion. Its influence in plants. And this allowed superiority of some animal forms to others is, in itself argument against the second error above named, that of attributing the sensation of beauty to the perception of expedient or constructive proportion. For everything that God has made is equally well constructed with reference to its intended functions. But all things are not equally beautiful. The megatherium is absolutely as well proportioned, with the view of adaptation of parts to purposes, as the horse or the swan; but by no means so handsome as either. The fact is, that the perception of expediency of proportion can but rarely affect our estimates of beauty, for it implies a knowledge which we very rarely and imperfectly possess, and the want of which we tacitly acknowledge.