This theory assumes the universe to be eternal. There is nothing extra, or antemundane. There is but one substance, and that substance is matter. Matter, however, has an active and passive principle. Life and rationality are among its attributes or functions. The universe, therefore, is a living whole pervaded by a principle not only of life but of intelligence. This hylozoic doctrine, some modern scientific men, as Professor Tyndall, seem inclined to adopt. They tell us that matter is not the dead and degraded thing it is commonly regarded. It is active and transcendental. What that means, we do not know. The word transcendental is like a parabola, in that there is no knowing where its meaning ends. To say that matter is transcendental, is saying there is no telling what it is up to. This habit of using words which have no definite meaning is very convenient to writers, but very much the reverse for readers. Some of the ancient Stoics distinguished between the active and passive principles in the world, calling the one mind, the other, matter. These however were as intimately united as matter and life in a plant or animal.