potent virtuality. Claude Bernard, who has repeated Coste's ideas on this subject, dwells strongly on the guiding force which is in the egg, and those savants who agree with Robin in denying this force, so far as it acts on the totality of elements in the embryo, regard it at least as shared, distributed, and acting in each of these elements separately, which, at bottom, is the same thing. We see, in any case, that there is in the inmost depth, and there dates from the most rudimentary sketch of the organized being, the fixed and formed idea of those differences in choice and those sympathies in work whose system shall build up the individual. The differential coefficient of organized matter is thus of a far higher order than that of mineral matter. It is this which is a distinct and peculiar result from the impotence which experimental science betrays more plainly every day, when attempting to convert physico-chemical activities into energies of the vital order. Even could this conversion really be effected, and it is not metaphysically impossible that it might be, the existence of a spiritual principle of differentiation would be in no wise put in doubt. Hitherto, at least, such a conversion seems beyond the reach of man.
Something that yet more completely baffles his research, while commanding too his highest admiration, is the supreme degree of complexity together with refinement of that energy which is the soul. Human thought is the sum of all the forces of Nature, because it assimilates them all, while distinguishing between them, by the work that it performs upon sensations. Sensations are to thought what food is to growth. Growth is not a result of feeding; thought is not a result of sensations. Nutrition, in shaping the living organs, determines the differentiation of the concrete forms in the individual's substance; thought, in shaping general ideas, determines the differentiation of the abstract forces in the world. Thus thinking energy is as much superior to sensations as nutritive energy is to aliments. In another order of thought, we might compare the soul to a paper covered with writing in sympathetic ink. At ordinary temperatures, the letters are unseen, but they appear in fine color whenever brought near the fire. So the soul has within itself dim marks and confused shapes which sensation tints and brightens. We have seen that, in the mucous drop, a two hundred and fiftieth part of an inch through, called the ovule, the forces and tendencies of the whole nutritive and intellectual life of man lie prisoned and asleep. So, too, in that force without form or extension, which is the soul, there dwells a miniature picture of the whole universe, and, by some mystic grace of God, a dream, as it were, of that God himself. Thought consists in becoming acquainted with all the details of that picture in little, and unfolding its meaning. Thus, that which makes the whole reality of material things is form, and form, such as it is shown to us in the world, is at once a principle of differentiation and a principle of agreement; in other words, it is the work of an intelligence. Body and motion are mere phenomena. The
