consequence for the purpose in hand, that anything corresponding to these concepts actually exists. If, however, one asserts that atoms really exist, or that reality is constituted in one way or another, then one has passed to the plane of metaphysics. It is clear, then, that the logical distinction between science and metaphysics appears in this, that metaphysics, the endeavor to know 'reality,' needs the predicate of existence, while science does not.
The question arises, why should not he, to whom the concept of an Absolute seems demanded by the facts of experience, treat this concept as the physicist treats the concept of the atom? And so far as I can see there is only an emotional reason why he should not do so. For the question is not whether there is reality, but whether in a given concept we have a true account of it.
Now metaphysics is anxious to be 'scientific' in every possible way, and among students of metaphysics we have those who are cool-blooded and critical, and those who warm to their tasks with emotional energy. It should not be in the least surprising if the former type of philosopher follows the example of science, and the second type alone continues to cling to the existential predicate. And in view of the great and increasing prestige of science, metaphysics, in the sense above explained, may become of less and less consequence in the world of thought. And if this comes to pass, as there is much reason to expect, we shall have science and the natural view of the world which we find in pure experience. This would be a verification of the predictions of Avenarius.
The fourth section, entitled 'Suggestions toward a Concept of Experience,' proposes a point of view which might be of service to the student of history, particularly the student of the history of theories of reality. This follows the theory that Avenarius has put forward in his essay 'Der Menschliche Weltbegriff.' It is a concept of a history of 'pure experience,' beginning in an animistic stage of culture and continuing until the animism which at the beginning had the character of undoubted fact, has been entirely eliminated from experience and from theory. The contention of Avenarius is that when this process of rejecting animism is completed, the theory of idealism must disappear. This concept is the concept of a genuine history, in which theories of reality have been determined by the fund of animism not yet rejected.
Finally, in the fifth and last section, I take up some contemporary discussions of pure experience. Professor William James has recently published his conviction that consciousness as a kind of stuff or entity does not exist. He believes that in dropping the idea of such an entity he is getting rid of the last remnant of the idea of the soul. To one who has in mind the theories of Avenarius,
