In ultimate analysis, the consciousness of the ‘Ego,’ and notably the opposition of the ‘Ego’ and the ‘non-Ego,’ is an illusion of the senses and a fallacy of thought. Every organism is related to a species, and, over and above that, to the universe. It is the direct material continuation of its parents; it is itself continued directly and materially in its descendants. It is composed of the same materials as the whole environing world; these materials are constantly penetrating into it, transforming it, producing in it all the phenomena of life and consciousness. All the lines of action of the forces of nature are prolonged in its interior; it is the scene of the same physical and chemical processes in action throughout the universe. What pantheism divines and clothes in needlessly mystic words is clear, sober fact, namely, the unity of nature, in which each organism is also a part related to the whole. Certain parts are more nearly connected; others are more separated from one another. Consciousness perceives only the closely-knit parts of its physical basis, not those more remote. Thus it falls into the illusion that the parts near together alone belong to it, and that the more distant are strangers to it, and to consider itself as an ‘individuum,’ confronting the world as a separate world or microcosm. It does not observe that the ‘I,’ so rigidly posited, has no fixed limits, but continues and spreads beneath the threshold of consciousness, with an ever-diminishing distinctness of separation, to the extreme depths of nature, till it blends there with all the other constituents of the universe. We may now resume much more briefly the natural history of the ‘I’ and the ‘not-I,’ and present it in a few formulæ. Consciousness is a fundamental quality of living matter. The highest organism itself is only a colony of the simplest organisms--that is to say, of living cells--differentiated diversely in order to qualify the colony for higher functions than the simple cell can accomplish. The collective or ego-consciousness of the colony is composed of the individual consciousness of the parts. The ego-consciousness has an obscure and disregarded part which relates to the vital functions of the cells, or the cœnæsthesis, and a clear, privileged part which is attentive to the excitations of the sensory nerves, and to the voluntary activity of the muscles, and which recognises them. Clear consciousness learns from experience that acts of will precede voluntary movements. It arrives at the assumption of causality. It observes that the sensorial excitations are not caused by anything contained in itself. It is compelled, in consequence, to transfer this cause, the assumption of which it cannot renounce, elsewhere, and is necessarily first brought by this to the presentation of a ‘not-I,’ and afterwards to the development of this ‘not-I’ into an apparent universe.