it was not till the seventeenth century that the new light really began to spread and brighten. One of the surest signs that an idea or feeling is coming to the surface of consciousness—surer than the appearance of one or two new words—is the tendency of an old one to form compounds and derivatives. After the Reformation we notice growing up in our language a whole crop of words hyphened with _self_; such are _self-conceit_, _self-liking_, _self-love_, and others at the end of the sixteenth century, and _self-confidence_, _self-command_, _self-contempt_, _self-esteem_, _self-knowledge_, _self-pity_, ... in the next. From a full list of such words as the above the historical student of words and their meanings could almost predict, apart from any other source of knowledge, the appearance at about this time of some philosopher who should do intellectually to the cosmos what Copernicus and Kepler had already done astronomically—that is, turn it inside out. And in Descartes, with his doctrine of “Cogito, ergo sum”, we do, in fact, find just such a philosopher. His influence was immense. Practically all philosophy since his day has worked outwards from the thinking self rather than inwards from the cosmos to the soul. In England, not long afterwards, we find the brand-new expressions, ‘the _ego_’ and _egoism_, coming into the language from French philosophy, while the English thinker, Locke, adopts the new (1632) word _consciousness_, defining it as ‘perception of what passes in a man’s own mind’, and at the same time impresses on the still newer _self-consciousness_[49] its distinctive modern meaning.