text: Our Stoic philosophers, as you know, declare that there are two things in the universe which are the source of everything, – namely, cause and matter. Matter lies sluggish, a substance ready for any use, but sure to remain unemployed if no one sets it in motion. Cause, however, by which we mean reason, moulds matter and turns it in whatever direction it will, producing thereby various concrete results. Accordingly, there must be, in the case of each thing, that from which it is made, and, next, an agent by which it is made. The former is its material, the latter its cause.