Darwin was not alone in his endeavour to prove that there exists no essential difference between man and beast; some have even asserted that the intelligence of certain animals is not only equal to, but at times, superior to that of man. We must be on our guard, however, against those numerous anecdotes which have led even philosophers astray; we will also divest our minds of prejudice and preconceived notions, that we may introduce some order into ideas which have been disturbed by superficial observers and the makers of false systems, those enemies of true science; let us candidly own the smallness of our knowledge concerning the mind of an animal; we do not in the least know how they philosophise, nor how an ox recognises his stable door. Instead of having recourse to animals and seeking to draw parallels between their mental faculties and ours, let us examine ourselves to find out what passes in our own minds. We shall then discover that we never in reality perceive anything unless we can distinguish it from other things by means, if not of a word, yet of a sign; that is till we have passed through the four stages of sensation, perception, conception, and more important than all, for our present purpose, of naming. When it is once acknowledged that concepts are impossible without words, and that man alone amongst organised beings possesses the power of language, and that the mental faculties of animals are different from ours in kind, and not only in degree, it naturally follows that a genealogical descent of man from animals is an impossible assumption. Formerly, in comparing the characteristics of man and animals it was contended that the latter were ruled by instinct in place of the reason which was the attribute of the former; and although an affirmation is not an explanation it appeared sufficiently plausible and was accepted. But the fact is that both man and beast possess instinct. If the spider weaves his net by instinct, a child takes his mother’s breast also by instinct; both are with regard to instinct at one level. Man involuntarily extends his arm to protect himself if he suddenly perceives an object near him on the point of striking him. “If we tear a spider’s web, and watch the spider first run from it in despair, then return and examine the mischief and endeavour to mend it. Surely we have the instinct of weaving controlled by observation, by comparison, by reflection, and by judgment.”[34] No one has hitherto succeeded in explaining and analysing the instinct said to be in animals. Cuvier[35] and other naturalists have compared it with habit.[36] This comparison gives an accurate notion of the frame of mind under which an instinctive action is performed, but does not necessarily explain its origin.