L CHAP. I. fion alone; nor is there lefs variety about the number and diftribution of the passions. The names we give to the various principles of action, have fo little precision, even in the best and pureft writers in every language, that, on this account, there is no fmall difficulty in giving them names, and arranging them properly. The words appetite, passion, affection, intereft, reason, cannot be faid to have one definite fignification. They are taken fometimes in a larger, and fometimes in a more limited sense. The fame principle is sometimes called by one of those names, sometimes by another; and principles of a very different nature are often called by the fame name. To remedy this confusion of names, it might perhaps feem proper to invent new ones. But there are fo few entitled to this privilege, that I fhall not lay claim to it; but shall endeavour to clafs the various principles of human action as diftinctly as I am able, and to point out their specific differences; giving them fuch names as may deviate from the common ufe of the words as little as poffible. There are some principles of action which require no attention, no deliberation, no will. Thefe, for diftinction's fake, we fhall call mechanical. Another class we may call animal, as they feem common to man with other animals. A third class we may call rational, being proper to man as a rational creature. CHAP. T CHA P. II. Inftinct. HE mechanical principles of action may, I think, be re- By inftinct, I mean a natural blind impulse to certain actions, without having any end in view, without deliberation, and very often without any conception of what we do. Thus a man breathes while he is alive, by the alternate contraction and relaxation of certain muscles, by which the cheft, and of confequence the lungs, are contracted and dilated.. There is no reason to think, that an infant new-born, knows that breathing is neceffary to life in its new state, that he knows how it must be performed, or even that he has any thought or conception of that operation; yet he breathes as foon as he is. born with perfect regularity, as if he had been taught, and got the habit by long practice. By the fame kind of principle, a new-born child, when its stomach is emptied, and nature has brought milk into the mother's breast, fucks and swallows its food as perfectly as if it knew the principles of that operation, and had got the habit of working according to them.. Sucking and swallowing are very complex operations. Anatomists describe about thirty pairs of muscles that must be employed in every draught. Of those muscles, every one must be served by its proper nerve, and can make no exertion but by fome influence communicated by the nerve. The exertion of all those muscles and nerves is not fimultaneous. They must CHAP. II. fucceed CHAP. II. fucceed each other in a certain order, and their order is no less neceffary than the exertion itself. This regular train of operations is carried on according to the nicest rules of art, by the infant, who has neither art, nor science, nor experience, nor habit. That the infant feels the uneafy sensation of hunger, I admit; and that it fucks no longer than till this fenfation be removed. But who informed it that this uneafy fenfation might be removed, or by what means? That it knows nothing of this is evident; for it will as readily fuck a finger, or a bit of stick, as the nipple. By a like principle it is, that infants cry when they are pained or hurt; that they are afraid when left alone, especially in the dark; that they start when in danger of falling; that they are terrified by an angry countenance, or an angry tone of voice, and are soothed and comforted by a placid countenance, and by foft and gentle tones of voice. In the animals we are beft acquainted with, and which we look upon as the more perfect of the brute-creation, we see much the fame inftincts as in the human kind, or very fimilar ones, fuited to the particular state and manner of life of the animal. Besides thefe, there are in brute-animals inftincts peculiar to each tribe, by which they are fitted for defence, for offence, or for providing for themselves, and for their offspring. It is not more certain, that nature hath furnished various animals with various weapons of offence and defence, than that the fame nature hath taught them how to use them; the bull and the ram to butt, the horse to kick, the dog to bite, the lion to use his paws, the boar his tufks, the ferpent his fangs, CHAP. II. and the bee and wafp their fting. The manufactures of animals, if we may call them by that name, prefent us with a wonderful variety of inftincts, belonging to particular fpecies, whether of the focial or of the folitary kind; the nefts of birds, fo fimilar in their fituation and architecture in the fame kind, so various in different kinds; the webs of spiders, and of other spinning animals; the ball of the filkworm; the nefts of ants and other mining animals; the combs of wafps, hornets and bees; the dams and houses of beavers. The inftinct of animals is one of the moft delightful and inftructive parts of a moft pleasant study, that of natural history; and deferves to be more cultivated than it has yet been. Every manufacturing art among men was invented by fome man, improved by others, and brought to perfection by time and experience. Men learn to work in it by long practice, which produces a habit. The arts of men vary in every age, and in every nation, and are found only in those who have been taught them. The manufactures of animals differ from thofe of men in many striking particulars. No animal of the species can claim the invention. No animal ever introduced any new improvement, or any variation from the former practice. Every one of the fpecies has equal skill from the beginning, without teaching, without experience or habit. Every one has its art by a kind of inspiration. I do not mean that it is inspired with the principles or rules of the art, but with the ability and inclination of working in it to perfection, without any knowledge of its principles, rules or end. The CHAP. II. The more fagacious animals may be taught to do many things which they do not by instinct. What they are taught to do, they do with more or less skill, according to their fagacity and their training. But, in their own arts, they need no teaching nor training, nor is the art ever improved or loft. Bees gather their honey and their wax, they fabricate their combs and rear their young at this day, neither better nor worse than they did when VIRGIL fo fweetly fung their works. The work of every animal is indeed like the works of nature, perfect in its kind, and can bear the most critical examination of the mechanic or the mathematician. One example from the animal last mentioned may serve to illustrate this. Bees, it is well known, conftruct their combs with small cells on both fides, fit both for holding their store of honey, and for rearing their young. There are only three poffible figures of the cells, which can make them all equal and fimilar, without any useless interftices. These are the equilateral triangle, the fquare, and the regular hexagon. It is well known to mathematicians, that there is not a fourth way possible, in which a plane may be cut into little spaces that fhall be equal, fimilar and regular, without leaving any interftices. Of the three, the hexagon is the most proper, both for conveniency and strength. Bees, as if they knew this, make their cells regular hexagons. As the combs have cells on both fides, the cells may either be exactly oppofite, having partition against partition, or the bottom of a cell may reft upon the partitions between the cells on the other fide, which will ferve as a buttrefs to ftrengthen it. The last way is best for strength; accordingly, the bottom of each cell refts against the point where three partitions meet on the other fide, which gives it all the ftrength poffible. The |