216 NOTES. [BK. I.
every investigation is for the purpose of knowing some-
thing, and as we cannot be said to know before we can comprehend wherefore a thing is what it is, (comprehend, that is, its first cause,) so it is evident that we must thus study the laws of reproduction destruction and change, throughout nature, in order to be enabled to refer, for each subject of investigation, to the first causes of the phænomena. This argument seems to confine causation to natural operations in particular, that is, living bodies; but cause had then, as it has now, a far wider significa-
tion—besides essence, individual being, elements, and other admitted first causes, that of which anything is made, was said to be its cause, as bronze of a statue, silver of a goblet, and, in a general sense the maker is the cause of the production, and he who alters, of the change, &c. Thus, there was great latitude in the enumeration of first causes. Thales, the founder of this branch of philosophy, maintains that water is a first cause, because the earth rose from water. Anaxi-
menes and Democritus contend that, as air was before water, so it is rather to be regarded as the first cause of everything.
Hippasus and Heraclitus set it down as being fire;
and Empedocles, adding earth, adopted four elementary
causes; for he maintained, that these elements are un-
changeable and unproduceable, although capable of com-
bining with and separating from one another. He first
- Metaphysica, i. 3. 5. 8.