itself into an organized faculty of the species, and the organism feels subjectively, as a discomfort which may amount to pain, the warning that a pernicious influence is acting upon it, and that it has to avoid it. To escape from pain becomes one principal function of the organism, which it cannot insufficiently provide against or neglect without expiating that negligence by its ruin. In the human being processes take place not otherwise than as they have been here described. The hereditary organized experience of the species warns him of the noxiousness of influences to which he is frequently exposed. His outposts against naturally hostile forces are his senses. Taste and smell give him, as to repulsive chimiotactic matter, the impressions of nausea and of stench; the different kinds of skin-sensations make him aware, through sensations of pain, heat, or cold, that a given contact is unfavourable to him; eye and ear place him on his guard, by loud, shrill, discordant sensations, against the mechanical effects of certain physical phenomena. Finally, the higher cerebral centres respond to recognised noxious influences of a composite nature, or to the representation of them by an equally composite reaction of aversion in different degrees of intensity, from simple discomfort to horror, indignation, dismay, or fury. The vehicle of this hereditary, organized, racial experience is the unconscious life; to it is confided defence against simple, frequently recurring noxious influences. Nausea at intolerable tastes, repugnance to insufferable smells, the fear of dangerous animals, natural phenomena, etc., have become for it an instinct to which the organism abandons itself without reflection--_i.e._, without the intervention of consciousness. But the human organism learns to distinguish and avoid not only all that is directly prejudicial to itself; it acts in the same way with regard to that which menaces it not as an individual, but as a racial being, as a member of an organized society; antipathy to influences injurious to the maintenance or prosperity of the society becomes in him an instinct. But this enriching of organized unconscious cognition represents a higher degree of development than many human beings attain to. The social instincts are those that a man acquires last of all, and, in conformity to a known law, he loses them first when he retrogrades in his organic development. Consciousness has occasion to declare the dangerous nature of phenomena, and to defend the organism against it, only if these phenomena are either quite new, or very rare, so that they cannot be hereditarily recognised and dreaded; or if they enclose in themselves many different elements, and do not act directly, but only by their more or less remote consequences, so that to know them exacts a complex activity of representation and judgment.