Waking and sleeping are the day and night sides of organic life, during which alternations an animal is placed in different relations to the external world, and to these alternations all organisms are subject. The completeness and independence of each individual organism, are in exact ratio to the number and completeness of the organs it develops; and thus the locomotive animal has the advantage of the plant or the zoophyte, while, of the animal kingdom, man is the most complete and independent; and, although still a member of the universal whole, and therefore incapable of isolating himself, yet better able than any other organism to ward off external influences, and comprise his world within himself. But, according to Dr. Ennemoser, one of the consequences of this very completeness is a weak and insignificant development of instinct; and thus the healthy, waking, conscious man, is, of all organisms, the least sensible to the impressions of this universal inter-communication and polarity; although, at the same time, partaking of the nature of the plant and the animal, he is subject, like the first, to all manner of atmospheric, telluric, and periodic influences; and frequently exhibits, like the second, peculiar instinctive appetites and desires, and, in some individual organizations, very marked antipathies and susceptibilities with regard to certain objects and influences, even when not placed in any evident relation with them. According to this theory, sleep is a retrograde step—a retreating into a lower sphere; in which condition, the sensuous functions being in abeyance, the instincts somewhat resume their sway. “In sleep and in sickness,” he says, “the higher animals and man fall in a physico-organical point of view, from their individual independence, or power of self-sustainment; and their polar relation, that is, their relation to the healthy and waking man, becomes changed from a positive to a negative one; all men, in regard to each other, as well as all nature, being the subjects of this polarity.” It is to be remembered, that this theory of Dr. Ennemoser’s was promulgated before the discoveries of Baron von Reichenback in magnetism were made public, and the susceptibility to magnetic influences in the animal organism, which the experiments of the latter go to establish, is certainly in its favor; but while it pretends to explain the condition of the sleepers, and may possibly be of some service in our investigations into the mystery of dreaming, it leaves us as much in the dark as ever, with respect to the cause of our falling into this negative state; an inquiry in which little progress seems to have been hitherto made.