This page needs to be proofread.

PSYCHOLOGICAL PHILOSOPHIES. 435 not only to individual persons, but to the whole of Nature, except such articles of human construction as were obviously lifeless. There arose accordingly the theory of an Anima Mundi ; a theory which Virgil beautifully expresses in lines which he puts into the mouth of Father Anchises in the Elysian Fields (Mneid vi., 724-734). We may call it, from an expression there used, the Hens agitat molem theory. From this Universal Soul or Mind individual persons were supposed to receive a particle or spark, divince particulam aura, as Horace calls it, on their coming into being. It was the source of their immortality, their indefeasible title to Heaven. This theory is now chiefly current in theology and poetry. It is probably the theory intended to be reformulated by Leibniz in his phrase Monad of Monads, applied to God, and also by Wordsworth in his Soul of our Souls, and safeguard of the World ! (Excursion, book iv., line 28). All common-sense people know what a Soul or a Mind is, though no one else does. But let me not be thought for a moment to disparage or undervalue this use of the terms. Nothing can be farther from my thought than that. It is as explanatory terms, as terms in which a philosophic or scientific theory may be expressed, that they are (in my opinion) useless. As used for expressing and enforcing moral and religious truths, apart from analysis and specu- lation, they are, by dint of long and complex association, priceless and indispensable. 2. As terms of philosophy or science they must be held to have given place to a new form or modification of themselves, namely, to the second theory I have mentioned, the theory of the Ego, when Descartes laid down as a self-evident truth, and one of the corner-stones of his philosophy, the famous dictum, Cogito ergo sum. Strictly, modern philosophy begins with that dictum, as the first distinct recognition of subjectivity ; that is to say, that immediate experience was the source and test of know- ledge. By the Cogito ergo sum, in place of the conception of a Soul or Mind, there was substituted the conception of an Ego or Self, the distinctive character of which was Self-consciousness. The fact expressed by the I think was immediately recognised by every one as his own indisputable experience ; and the inference drawn from it as causa cognos- cendi : Therefore I am, was also recognised as an indisputable statement of the reality of the agent, or causa existendi, of the thinking. But the nature of the Ego or Self was still undiscovered.