Our final answer, then, to the question which led us into this digression is this:--It is quite true that the material world exists: it is quite true that we believe in this existence, and always act in conformity with our faith. Whole books may be written in confirmation of these truths. They may be published and paraded in a manner which apparently settles the entire problem of perception. And yet this is not the right way to go to work. It settles nothing but what all men, women, and children have already settled. The truths thus formally substantiated were produced without an effort--every one has already got from Nature at least as much of them as he cares to have; and therefore, whatever their importance may be, they cannot, with any sort of propriety, be made the subjects of conveyance from man to man. We must either leave the problem altogether alone, (a thing, however, which we should have thought of sooner,) or we must adopt the speculative treatment. The argument, moreover, contained in the preceding paragraph, appears to render this treatment imperative; and accordingly we now return to it, after our somewhat lengthened digression. We must take up the thread of our discourse at the point where we dropped it. The crisis to which the discussion had conducted us was this; that the existence of matter could not be believed in _at all_. The psychological analysis necessarily lands us in this conclusion: for the psychological analysis gives us, for matter, nothing but matter _per se_. But matter _per se_ is what no man does or can believe in. We are reluctant to reiterate the proof; but it is this: to believe in the existence of matter _per se_ is to believe in the existence of matter liberated from perception; but we, cannot believe in the existence of matter liberated from perception, for no power of thinking will liberate matter from perception; therefore, we cannot believe in the existence of matter _per se_. This argument admits of being exhibited in a still more forcible form. We commence with an illustration. If a man believes that a thing exists as one thing, he cannot believe that this same thing exists as another thing. For instance, if a man believes that a tree exists as a tree, he cannot believe that it exists as a house. Apply this to the subject in hand. If a man believes that matter exists as a thing _not_ disengaged from perception, he cannot believe that it exists as a thing _disengaged_ from perception. Now, there cannot be a doubt that the _only_ kind of matter in which man believes is matter _not_ disengaged from perception. He therefore cannot believe in matter _disengaged_ from perception. His mind is already preoccupied by the belief that matter is _this one thing_, and, therefore, he cannot believe that it is _that other thing_. His faith is, in this instance, forestalled, just as much as his faith is forestalled from believing that a tree is a house, when he already believes that it is a tree.