signified, than birds; which seems evidently to be the case. Sagacious quadrupeds may therefore be said to resemble dumb persons arrived at adult age, who are possessed of much knowledge, which yet they cannot express, except by gestures, by dumb show: whereas parrots, as before remarked, resemble children; these having many words with very little knowledge annexed to them.
Apes and monkeys, of the several kinds, seem to approach nearest to man, in the general faculty of reasoning, and drawing conclusions; but in particular things, especially where instinct prevails, some other brutes far exceed them; as indeed such brutes do man himself in a few, on account of the peculiar acuteness of the sense of smell, and the same instinct.
I reckon the want of articulate sounds to be one of the reasons why brutes are so much inferior to men in intellectual capacities; because it appears, from the foregoing and other considerations of the same kind, that it is so. But this is no imperfection upon the whole. The proportional smallness of their brains, the texture of these, their instincts, and their external circumstances, are such, that they do not want language much; that they could make no great use of it, had they proper organs for speaking; and that they would probably be losers, upon the whole, by having it. The efficient and final causes are here suited to each other, as in all other cases; so that no circumstance can be changed for the better, cæteris manentibus.
Fourthly, Let us come to the instinctive powers of animals. These are a point of a very difficult consideration. They are evidently not the result of external impressions, by means of the miniatures of these, their associations and combinations, in the manner according to which I have endeavoured to shew that the rational faculties of mankind are formed and improved; and yet, in the instances to which they extend, they very much resemble the rational faculties of mankind. Animals, in preparing and providing for themselves and their young, in future exigencies, proceed in the same manner as a person of good understanding, who foresaw the event, would do; and this, even though they be a little put out of their way. And in this they much resemble persons of narrow capacities and acquisitions, who yet excel greatly in some particular art or science; of which there are many instances. Such persons shew great ingenuity in the things to which they are accustomed, and in some others that border upon them within certain limits, so as to shew great ingenuity still, though put a little out of their way; but if they be put much out of their way, or questioned about things that are entirely foreign to the art or science in which they excel, they are quite lost and confounded.
Let us suppose this to be the case, and then the inquiry concerning instinct in brutes will be reduced to this; viz. by what means the nervous systems of brutes are made to put on dispo-
