III. ANAXIMENES.--This philosopher was also a native of Miletus, and is said to have been a hearer or pupil of Anaximander. As we have said, the [19] tendency of the later members of the school was towards emphasising the _motive_ side of the supposed underlying principle of nature, and accordingly Anaximenes chose Air as the element which best [18] represented or symbolised that principle. Its fluidity, readiness of movement, wide extension, and absolute neutrality of character as regards colour, taste, smell, form, etc., were obvious suggestions. The breath also, whose very name to the ancients implied an identity with the life or soul, was nothing but air; and the identification of Air with Life supplied just that principle of productiveness and movement, which was felt [20] to be necessary in the primal element of being. The process of existence, then, he conceived as consisting in a certain concentration of this diffused life-giving element into more or less solidified forms, and the {15} ultimate separation and expansion of these back into the formless air again. The contrary forces previously used by Anaximander--heat and cold, drought and moisture--are with Anaximenes also the agencies which institute these changes. This is pretty nearly all that we know of Anaximenes. So far as the few known facts reveal him, we can hardly say that except as supplying a step towards the completer development of the _motive_ [22] idea in being, he greatly adds to the chain of progressive thought.