for being ignorant of the history of philosophy and scientific opinion generally.

But this type of mind is easily reduced to silence. It knows where its bread is buttered and that, if it boldly advocated materialism or recognized its strength it would not be wanted in a philosophic chair where the interests of religious faith have to be defended, or at least not antagonized. He can conjure up a meaning of the term which he can deny and save himself the danger of friction with those in authority. The fact is the term "materialism" does service for two totally different conceptions and unless this is recognized, the philosopher will have things all his own way. These two conceptions define or determine two distinct types of materialism. They may be called naive and philosophical materialism. In the controversies of the past no such division has been adopted. Indeed the parties opposing materialism did not dare admit the two types, as it would embarrass them in the concealment of their views on immortality, about which they did not wish to say anything and which they did not dare oppose. They might permit the public to infer what they did not admit or believe, and they wanted to escape any defensive word for the theory.

Now it was naive materialism that the philosopher has always denied. He either did not deny philosophic materialism, or he evaded a confession of belief in it for the same reasons that led him to deny the naive form of it. Naive materialism is based upon sensation and the ideas which most men have when forming their ideas of things from it. It is closely related to one form of Realism, presentative Realism as distinct from the hypothetical. Presentative or naive Realism supposes that the external world is exactly as it appears in sensation. It asserts that we see things as they are and does not think that we get our knowledge of reality from inferences or by some internal faculty which is

above sense. It takes the world as it is revealed in sense perception. It is directly opposed to what is called Idealism which is supposed to deny the criterial nature of sensation in the judgments of reality and an external world. That is, Realism and Idealism are the two opposing theories regarding the nature of reality. Idealism is most closely associated with intellectual and non-sensory processes in the judgments of reality while Realism is more closely associated with sensation and sensory processes in those judgments. Realism assumes that the material world is rightly known in sensation and Idealism that it is rightly known only by intellectual and non-sensory processes. The opposition between them is quite radical.

Philosophic materialism, however, is not based upon sensation or any conception of reality dependent on sensation. It is as much based upon the intellectual processes as Idealism. In all its history it has eschewed sensation and sensory criteria for reality. The atoms of both the ancient and modern philosophers were supersensible, quite as supersensible as spirit. In that respect philosophic materialism is at one with Idealism and always has been. It would be as distinctly opposed to naive Realism as any form of Idealism.

The fact is that there are two pairs of antitheses here whose definition may clear up the confusion. One is the opposition between Materialism and Spiritualism and the other is that between Realism and Idealism. The first pair are metaphysical theories about the nature of reality; the second pair are epistemological theories about the source of our knowledge of reality. This distinction will mean that a Realist may be either a materialist or a spiritualist, and an idealist in the theory of knowledge may be either a materialist or a spiritualist in metaphysics. But there is no necessary antagonism between philosophical materialism and Idealism as usually held. It is only when a man

equivocates with the term Idealism, especially the historical and accepted meaning of the term, that he can find any opposition between it and philosophic materialism.

It was the result of Kant's reflections that this confusion arose. Kant recognized that it was Materialism and Spiritualism that were opposed to each other. But as his arguments about immortality resulted in an agnostic conclusion, the term Spiritualism was dropped as an unsustainable theory, and the meaning of the term Materialism was changed over to the sensational conception of the situation and Idealism opposed to it. Kant does not talk about Realism. He says little about Materialism other than that it is the correct antithesis to Spiritualism, while his adoption of Idealism and his silence about Realism leaves him with a tacit alteration of the term "materialism" in subsequent thought for an antithesis to Idealism, and that consecrated the naive sensory conception of it as the one which could easily be denied, while the philosopher could remain agnostic or silent on the question of immortality.

In the antithesis between Materialism and Spiritualism, if you deny Materialism, you must affirm Spiritualism and with it survival. If you deny Spiritualism and with it immortality you must affirm Materialism. In the antithesis between Realism and Idealism, the assertion of one denies the other. But considering that naive materialism or Realism and philosophical materialism are not convertible, the denial of naive ma-. terialism does not imply the truth of Spiritualism. Nor does it imply the falsity of philosophical materialism. The two theories may be as strictly opposed to each other as the other two antitheses. But it is the interest of the philosopher to deny "materialism" in order to escape the accusation of denying survival, and so he hits upon that conception of it which will save him

the necessity of argument on the latter issue and he can leave the plebs to infer what they please. It is philosophical materialism to which psychic research is opposed and whose strength it frankly concedes, from the standpoint of normal experience, and all scientific results in that field. It may also oppose naive materialism, but not because it fears its denial of immortality, but simply because it is idealistic in its theory of knowledge. The denial of sensational or naive materialism affirms Idealism, but it does not affirm Spiritualism. But the defender of Idealism is quite willing to have the plebs believe that it does affirm it, so that he may escape the duty to give further evidence. It is not naive materialism that the psychic researcher apologizes for, or defends from the standpoint of normal experience, but philosophical materialism and the philosopher who evades this issue is either ignorant of his calling or he is deliberately equivocating.

Nor does the philosopher who opposes materialism, when ignoring or ridiculing psychic research, gain anything by saying that he does so because materialism cannot explain consciousness. He knows that, if he admits consciousness to be a function of the organism, he gains nothing by denying naive materialism, and so he conjures up some way to say that materialism has never reduced consciousness to any equivalent in physical phenomena. He denies the application of the conservation of energy to mental phenomena. He denies the causal nexus, the material causal nexus, between physical and mental phenomena. He asserts with great confidence that physiology, biology, and other sciences have not reduced and cannot reduce consciousness or mental phenomena to any physical equivalent. He expects by this either to prove the existence of soul or to enable him to evade the issue. He never seems to discover that, if you did so reduce it, you would absolutely prove the spirituali.tic theory. He does not

see that his own position does not carry survival with it and that he only paves the way for skepticism and agnosticism, which he thinks he has refuted by denying the success of reducing mental to physical phenomena. To make them interconvertible would be to make them identical in terms of the conservation of energy and that would be to make mental phenomena always existent, at least as parallel with physical or as continuous with it. That would be a conclusion which he either opposes or denies where it would be his interest to affirm it.

Now it must be emphasized that philosophical materialism does not depend on proving a nexus of the same kind between physical and mental phenomena. It does not depend on affirming that it can reduce mental phenomena to physical ones. Its problem is not primarily an explanatory one in that sense of the term. It is not "explaining" consciousness in terms of its antecedents. It is concerned with evidence for a fact; namely, the dependence of consciousness on the organism for its existence, not for its nature. The philosophical materialist may not know any more about the nature of consciousness than the opponent of materialism. He is not trying to "explain" consciousness in terms of antecedents or equivalents. He is occupied with an evidential problem. What he contends for is that all the evidence is for the fact that it is a function of the brain, whether he can tell how this is possible or not. It is not how it depends on the brain, but the fact of it that concerns him, and he maintains that all the facts and evidence of normal experience favors that view, and he will abide his time in determining how this is possible.

The man who asserts that we have not reduced consciousness to its physical equivalent is only equivocating or indulging in subterfuges, if he supposes that this has anything to do with the main question, which