The self which acts in a man is itself moved by forces which have long been familiar to common sense, without being understood except dramatically.  These forces are called the passions; or when the dramatic units distinguished are longish strands rather than striking episodes, they are called temperament, character, or will; or perhaps, weaving all these strands and episodes together again into one moral fabric, we call them simply human nature.  But in what does this vague human nature reside, and how does it operate on the non-human world?  Certainly not within the conscious sphere, or in the superficial miscellany of experience.  Immediate experience is the intermittent chaos which human nature, in combination with external circumstances, is invoked to support and to rationalise.  Is human nature, then, resident in each individual soul?  Certainly:  but the soul is merely another name for that active principle which we are looking for, to be the seat of our sensibility and the source of our actions.  Is this psychic power, then, resident in the body?  Undoubtedly; since it is hereditary and transmitted by a seed, and continually aroused and modified by material agencies.

Since this soul or self in the body is so obscure, the temptation is great to dramatise its energies and to describe them in myths.  Myth is the normal means of describing those forces of nature which we cannot measure or understand; if we could understand or measure them we should describe them prosaically and analytically, in what is called science.  But nothing is less measurable, or less intelligible to us, in spite of being so near us and familiar, as the life of this carnal instrument, so soft and so violent, which breeds our sensations and precipitates our actions.  We see today how the Freudian psychology, just because it is not satisfied with registering the routine of consciousness but endeavours to trace its hidden mechanism and to unravel its physical causes, is driven to use the most frankly mythological language.  The physiological processes concerned, though presupposed, are not on the scale of human perception and not traceable in detail; and the moral action, though familiar in snatches, has to be patched by invented episodes, and largely attributed to daemonic personages that never come on the stage.

Locke, in his psychology of morals, had at first followed the verbal rationalism by which people attribute motives to themselves and to one another.  Human actions were explained by the alleged pursuit of the greater prospective pleasure, and avoidance of the greater prospective pain.  But this way of talking, though not so poetical as Freud’s, is no less mythical.  Eventual goods and evils have no present existence and no power:  they cannot even be discerned prophetically, save by the vaguest fancy, entirely based on the present impulses and obsessions of the soul.  No future good, no future evil avails to move us, except—­as Locke said after examining the facts more closely—­when