By these are meant man's thoughts and feelings, and that they are different from the matter composing his body seems self-evident. Matter possesses size, weight, colour, shape, and hardness. Mind does not possess any of these. They have no conceivable meaning when applied to thoughts and feelings. Yet both mind and matter exist in man. We each feel conscious that we have something which _thinks_, and which we call mind; as well as something which _moves_, and which we call matter (_i.e._, our bodies); and that these are absolutely distinct from one another. And from the nature of the case this _inherent conviction_ is all we can appeal to. For mind, if it exists at all, being different from matter, is beyond the reach of ordinary scientific discovery. We cannot however be more certain of anything than of these inherent convictions, which form the basis of all our knowledge. Even the propositions of Euclid are only deductions from some other of our convictions, such as that the whole is greater than its part. Still the difficulty of understanding this compound nature in man, part mind and part body, has led some persons to adopt the theory of _materialism_. According to this there is no such thing as _mind_; what we call thoughts and feelings being merely complicated motions of the molecules of the brain. Now, that the mind and brain are closely associated together none will deny, but it does not follow that they are identical. The brain may be merely the instrument of the mind through which it acts. And though, as far as we know, the mind can never act without the brain, it may certainly have a separate existence, and possibly, under different conditions, may be able to act separately. It is in fact no more difficult to conceive of thought without a brain, than to conceive of thought with a brain. All we can say is, that within the range of our experience the two seem to be somehow connected together. Recent investigations, however, in what is called _telepathy_ (or thought-transference) seem to show that in some cases one mind can influence another _at a distance_, and without any material connection. And this (if admitted) proves that the mind is something more than a mere collection of particles of matter. Moreover materialism, to be consistent, must deny not only that man has a mind, but that he has anything immaterial at all; he must be matter in motion, and nothing else. But this is disproved by our _memory_, which convinces us that we are the _same_ persons now as we were ten years ago; yet we know that every particle of our bodies, including our brains, has changed in the interval. We must then have something immaterial which survives, in spite of everything material changing.