Now why I mention these two points is that when engaged in the intricacies of philosophic discussion, we are apt to overlook the vastness of the difference between this idealistic view and the ordinary view of the world, and to overlook the number of different propositions which the idealist must prove. It is, I think, owing to the vastness of this difference and owing to the number of different excellences which Idealists attribute to the universe, that it seems such an interesting and important question whether Idealism be true or not. But, when we begin to argue about it, I think we are apt to forget what a vast number of arguments this interesting question must involve: we are apt to assume, that if one or two points be made on either side, the whole case is won. I say this lest it should be thought that any of the arguments which will be advanced in this paper would be sufficient to disprove, or any refutation of them sufficient to prove, the truly interesting and important proposition that reality is spiritual. For my own part I wish it to be clearly understood that I do not suppose that anything I shall say has the smallest tendency to prove that reality is not spiritual: I do not believe it possible to refute a single one of the many important propositions contained in the assertion that it is so. Reality may be spiritual, for all I know; and I devoutly hope it is. But I take 'Idealism' to be a wide term and to include not only this interesting conclusion but a number of arguments which are supposed to be, if not sufficient, at least necessary, to prove it. Indeed I take it that modern Idealists are chiefly distinguished by certain arguments which they have in common. That reality is spiritual has, I believe, been the tenet of many theologians; and yet, for believing that alone, they should hardly be called Idealists. There are besides, I believe, many persons, not improperly called Idealists, who hold certain characteristic propositions, without venturing to think them quite sufficient to prove so grand a conclusion. It is, therefore, only with Idealistic arguments that I am concerned; and if any Idealist holds that no argument is necessary to prove that reality is spiritual, I shall certainly not have refuted him. I shall, however, attack at least one argument, which, to the best of my belief, is considered necessary to their position by all Idealists. And I wish to point out a certain advantage which this procedure gives me—an advantage which justifies the assertion that, if my arguments are sound, they will have refuted Idealism. If I can refute a single proposition which is a necessary and essential step in all Idealistic arguments, then, no matter how good the rest of these arguments may be, I shall have proved that Idealists have no reason whatever for their conclusion.
Suppose we have a chain of argument which takes the form: Since A is B, and B is C, and C is D, it follows A is D. In such an argument, though 'B is C' and 'C is D' may both be perfectly true, yet if 'A is B' be false, we have no more reason for asserting A is D than if all three were false. It does not, indeed, follow that A is D is false; nor does it follow that no other arguments would prove it to be true. But it does follow that, so far as this argument goes, it is the barest supposition, without the least bit of evidence. I propose to attack a proposition which seems to me to stand in this relation to the conclusion 'Reality is spiritual.' I do not propose to dispute that 'Reality is spiritual;' I do not deny that there may be reasons for thinking that it is: but I do propose to show that one reason upon which, to the best of my judgment, all other arguments ever used by Idealists depend is false. These other arguments may, for all I shall say, be eminently ingenious and true; they are very many and various, and different Idealists use the most different arguments to prove the same most important conclusions. Some of these may be sufficient to prove that B is C and C is D; but if, as I shall try to show, their 'A is B' is false the conclusion A is D remains a pleasant supposition. I do not deny that to suggest pleasant and plausible suppositions may be the proper function of philosophy: but I am assuming that the name Idealism can only be properly applied where there is a certain amount of argument, intended to be cogent.
The subject of this paper is, therefore, quite uninteresting. Even if I prove my point, I shall have proved nothing about the Universe in general. Upon the important question whether Reality is or is not spiritual my argument will not have the remotest bearing. I shall only attempt to arrive at the truth about a matter, which is in itself quite trivial and insignificant, and from which, so far as I can see and certainly so far as I shall say, no conclusions can be drawn about any of the subjects about which we most want to know. The only importance I can claim for the subject I shall investigate is that it seems to me to be a matter upon which not Idealists only, but all philosophers and psychologists also, have been in error, and from their erroneous view of which they have inferred (validly or invalidly) their most striking and interesting conclusions. And that it has even this importance I cannot hope to prove. If it has this importance, it will indeed follow that all the most striking results of philosophy—Sensationalism. Agnosticism and Idealism alike—have, for all that has hitherto been urged in their favour, no more foundation than the supposition that a chimera lives in the moon. It will follow that, unless new reasons never urged hitherto can be found, all the most important philosophic doctrines have as little claim to assent as the most superstitious beliefs of the lowest savages. Upon the question what we have reason to believe in the most interesting matters, I do therefore think that my results will have an important bearing; but I cannot too clearly insist that upon the question whether these beliefs are true they will have none whatever.
The trivial proposition which I propose to dispute is this: that esse is percipi. This is a very ambiguous proposition, but, in some sense or other, it has been very widely held. That it is, in some sense, essential to Idealism, I must for the present merely assume. What I propose to show is that, in all the senses ever given to it, it is false.
But, first of all, it may be useful to point out briefly in what relation I conceive it to stand to Idealistic arguments. That wherever you can truly predicate esse you can truly predicate percipi, in some sense or other, is, I take it, a necessary step In all arguments, properly to be called Idealistic, and, what is more, in all arguments hitherto offered for the Idealistic conclusion. If esse is percipi, this is at once equivalent to saying that whatever is, is experienced; and this, again, is equivalent, in a sense, to saying that whatever is, is something mental. But this is not the sense in which the Idealist conclusion must maintain that Reality is mental. The Idealist conclusion is that esse is percipere; and hence, whether esse be percipi or not, a further and different discussion is needed to show whether or not it is also percipere. And again, even if esse be percipere, we need a vast quantity of further argument to show that what has esse has also those higher mental qualities which are denoted by spiritual. This is why I said that the question I should discuss, namely, whether or not esse is percipi, must be utterly insufficient either to prove or to disprove that reality is spiritual. But, on the other hand, I believe that every argument ever used to show that reality is spiritual has inferred this (validly or invalidly) from 'esse is percipere' as one of its premisses; and that this again has never been pretended to be proved except by use of the premiss that esse is percipi. The type of argument used for the latter purpose is familiar enough. It is said that since whatever is, is experienced, and since some things are which are not experienced by the individual, these must at least form part of some experience. Or again that, since an object necessarily implies a subject, and since the whole world must be an object, we must conceive it to belong to some subject or subjects, in the same sense in which whatever is the object of our experience belongs to us. Or again, that, since thought enters into the essence of all reality, we must conceive behind it, in it, or as its essence, a spirit akin to ours, who think: that 'spirit greets spirit' in its object. Into the validity of these inferences I do not propose to enter: they obviously require a great deal of discussion. I only desire to point out that, however correct they may be, yet if esse is not percipi, they leave us as far from a proof that reality is spiritual, as if they were all false too.
But now: Is esse percipi? There are three very ambiguous terms in this proposition, and I must begin by distinguishing the different things that may be meant by some of them.
And first with regard to percipi. This term need not trouble us long at present. It was, perhaps, originally used to mean 'sensation' only; but I am not going to be so unfair to modern Idealists—the only Idealists to whom the term should