The struggle which we are now maintaining against the philosophers of matter is as ancient as science, and was going on, nearly in the same terms, more than two thousand three hundred years ago. About five hundred years before the Christian era was born at Clazomenae, a city of Ionia, the son of Eubulus, who was to become famous by the name of Anaxagoras. He fixed his abode at Athens, and the Athenian people gave him a glorious surname,--they called him _Intelligence_. On what account? There were taught at that time doctrines which explained the world by the transformations of matter rising progressively to life and thought, without the intervention of a mind. The philosopher Anaximander gave out that the first animals had their origin in the watery element, and became modified by living in drier regions, so that man was only a fish slowly transformed. "I am quite willing to grant it," replied Anaxagoras; "but for your transformations there must be a transforming principle. Matter is the material of the world, no doubt; but it could not produce universal order except as ruled by intelligence." The Athenians admired this discovery. For us, Gentlemen, the discovery has been made a long while. Let us not then be talking in this discussion about modern science and the lights of the age. Our natural history is much advanced as compared with that of the Greeks; but the vital question has not varied. Does nature manifest the intervention of a directing mind, or do we see in it only a fortuitous aggregation of atoms? Intelligence radiates from the face of nature, and it is in vain that men endeavor to veil its splendor. Nevertheless I consent to forget all that has just been said, in order to intrench myself in an argument, which of itself is sufficient for the object we have in view to-day. Our object is to prove that material science does not contain the explanation of all the realities of the universe. Even though they had succeeded in persuading us that there is no intelligence in nature, it would still be necessary to explain the origin of that intelligence which is in us, and the existence of which cannot be disputed. Whence proceeds the mind which is in ourselves?