"The early philosophers as a rule formulated the originative principle ((Greek) _arche_) of all things under some material expression. By the originative principle or element of things they meant that of which all {5} existing things are composed, that which determines their coming into being, and into which they pass on ceasing to be. Where these philosophers differed from each other was simply in the answer which they gave to the question what was the nature of this principle, the differences of view among them applying both to the number, and to the character, of the supposed element or elements. "Thales, the pioneer of this philosophy, maintained that _Water_ was the originative principle of all things. It was doubtless in this sense that he said that the earth rested on water. What suggested the conception to him may have been such facts of observation, as that all forms of substance which promote life are moist, that heat itself seems to be conditioned by moisture, that the life-producing seed in all creatures is moist, and so on." Other characteristics of water, it is elsewhere suggested, may have been in Thales' mind, such as its readiness to take various shapes, its convertibility from water into vapour or ice, its ready mixture with other substances, and so forth. What we have chiefly to note is, that the more unscientific this theory about the universe may strike us as being, the more completely out of accord with facts now familiar to everybody, the more striking is it as marking a new mood of mind, in which _unity_, though only very partially suggested or discoverable by the senses, is {6} preferred to that infinite and indefinite _variety_ and _difference_ which the senses give us at every moment. There is here the germ of a new aspiration, of a determination not to rest in the merely momentary and different, but at least to try, even against the apparent evidence of the senses, for something more permanently intelligible. As a first suggestion of what this permanent underlying reality may be, _Water_ might very well pass. It is probable that even to Thales himself it was only a symbol, like the figure in a mathematical proposition, representing by the first passable physical phenomenon which came to hand, that ideal reality underlying all change, which is at once the beginning, the middle, and the end of all. That he did not mean Water, in the ordinary prosaic sense, to be identical with this, is suggested by some [10] other sayings of his. "Thales," says Aristotle elsewhere, "thought the whole universe was full of gods." "All things," he is recorded as saying, "have a _soul_ in them, in virtue of which they move other things, and are themselves moved, even as the magnet, by virtue of its life or soul, moves the iron." Without pushing these fragmentary utterances too far, we may well conclude that whether Thales spoke of the soul of the universe and its divine indwelling powers, or gods, or of water as the origin of