destroyed, neither increased nor diminished in number, by natural forces; that matter may consequently change endlessly in form and force in direction, but that the quantity of matter and the amount of force in the world are always the same,— are scientific conceptions so grand that the modern world is apt to believe that the ancient world could not have possessed them. There can be no doubt, however, that all these ideas are more than two thousand years old. They lay at the very foundation of the atomic philosophy. All that the most recent science has done in regard to them has been to verify them in particular instances by exact experiments. Modern men of science are apt to imagine that this is really for the first time to have established them. But this is not the case. No general truth can be established by experiment, or be seen by the eye or touched by the hand. It can only be reached by thought, and thought reached all the general truths in question really, although vaguely, very long ago. I cannot admit that there is an essential difference even in method between the ancient and the modern atomists. To say that the former assumed their theory, and unfolded its applications by reasoning down from it, and that the latter reverse the process and reason up to it by induction, is thoroughly inaccurate. The ancients proceeded so far by induction; it is only so far that the moderns can proceed by it.

According to the theory we are considering, the ultimate elements of things are body and spacethe atom and the void. Space is limitless, immeasurable; the gleaming thunderbolt speeding through it for ever would fail to traverse it, or even in the least to lessen what of it remained. The atoms are numberless, ungenerated, infrangible, unchangeable, indestructible. Their only qualities are form, magnitude, and density; and their variations in these respects account for the diverse qualities in the diverse objects of the universe. This theory ought at once to raise the questions,-What proof is there that these indivisible atoms are really ultimate in any other sense than that they are the primary constituents of body? What evidence is there that they are selfexistent? Why should reason stop with them and seek no explanation of them? How is it that they account not only for other things but for themselves? But to these questions we get no rational replies. These are questions which materialism. has never dared fairly to confront and grapple with. It has always shown, on the contrary, by its evasion of them, a certain vague and confused consciousness that there is something unsound and insecure at its very basis. Materialism, which is so bold in hypothetical explanations of things, is strangely timid in self-criticism.

Epicurean materialism, like all materialism,

affirms matter to be eternal; but when you seek a reason for the assertion, you can find none save that it is impossible something should come from nothing. That is to say, Epicurean materialism, like all materialism, starts with an illegitimate application of the principle of causality, or of its axiomatic expression,-" Nothing which once was not could ever of itself come into being." By the great body of thoughtful men, both in ancient and modern times, this has been taken to mean merely that nothing can be produced without an adequate cause; that every change demands a full explanation; that every phenomenon must have a sufficient ground. Epicurus, Lucretius, and materialists in general, assume it to mean that, since matter is, matter must always have been; that matter could never have been created; that the world was uncaused. If the assumption be a mere assumption -if no reason be given for this extraordinary interpretation-it is a most inexcusable procedure. Now, vast as the literature of materialism is, you will search it through in vain, from the fragments of Democritus to the last edition of Büchner, for a single reason, a single argument, to justify this manifest begging of the whole question. Instead, you will find only poetical and rhetorical reiterations of the assumption itself, diffuse assertions of the eternity, indestructibility, and self-existence of matter.

Materialism thus starts with an irrational

assumption, the true character of which it endeavours to conceal by appealing merely to the imagination.

It was not enough, however, for the purpose which the atomic atheists had in view that they should merely suppose the atoms to be eternal. It was further necessary for them to suppose that the atoms, although without colour or any property perceptible to the senses, had every variety of shape, and the particular sizes, required to enable them to compose the vast variety of things in the universe. If they had all been alike, they could, according to the admission of the atomists themselves, have formed no universe. But, curiously enough, while admitting that they did not see that they were bound to ask and to explain how the atoms came to be unlike; how some of them came to be smooth and round, others to be cubical, others to be hooked and jagged, &c.; and, in a word, how they all came to be just so shaped as to be able collectively to constitute an orderly and magnificent universe. Still more curiously, all materialism down to this day has been afflicted with the same blindness. My belief is, that if it were not thus blind it would die. The light would kill it. It would see that the atoms on which it theorised could not be really ultimate, and implied the power and wisdom of God.

The Epicurean materialists found that, even

when they had imagined their atoms to be eternal, and to be endowed with suitable shapes, their hypothesis would not work. They found that they required to put something more into their atoms before they could get a universe from them. For they had to ask themselves, How do the atoms ever meet and combine? It is obvious that if they all fall in straight lines, and with the same rapidity, they can never meet. Hence Democritus said that the larger ones move faster than the smaller ones, and that this is the cause of their collision and combination. But, objected Aristotle, that cannot be the case in a perfect vacuum where no resistance whatever is offered to the fall of bodies, whether large or small. There all bodies must fall with equal rapidity. The Epicureans admitted that this objection was fatal to the atomic theory as presented by Democritus. Still, as they denied any intelligent First Cause, they had to devise some hypothesis of the contact and aggregation of the atoms. They imagined, accordingly, a small deviation of the atoms from a straight line. But how can this deviation be produced? Not from without the atoms, since nothing but void space is supposed to be without them, and all divine or supernatural interposition is expressly rejected. The Epicureans had therefore no other resource than to hold that the atoms were endowed with a certain spontaneity,