and as such may be compared with the great achievements of Newton and Ampère in explaining the rotatory motions observed in planets and magnets as the consequence of forces acting in the straight line between the points. It is obvious that this rectilinear action is hypothetical. It is certain that the real motion is that of a rotation of the bodies, as nothing else is observed nor observable. The geometric construction is purely ideal; the observed rotations are explained on the assumption of a force acting according to the law of inverse squares, another ideal; this radius vector passing over equal areas in equal times was never seen by mortal eye. All we know is, that if there were a radius vector, it would describe equal areas in equal times; and that if there were an attractive force acting along the straight line between the points, it would be represented by such a law. In like manner we may say, if masses are composed of atoms, and if there is an ethereal medium between them, the mathematical explanations of observed facts which are based on such assumptions are exact; but we can never know whether the assumptions themselves have any correspondent reals. The Matter we know, is the Matter we feel.

CHAPTER V.

THE SOLUTION.

95. WE have now before us, if not the final solution of a problem which can never finally be solved so long as Experience is progressive, at least a "first approximation." Having eliminated the metempirical aspects of the question, there only remain the facts of Experience to enumerate and classify, and the question is answered. Those lofty minds who despise the poor results of a science which can only classify feelings and the symbols. of feelings, will, of course, be scornful of this meagre answer. Their question is, What is Matter apart from Feeling? and our answer does not touch that. We, who maintain that all knowledge whatever is only virtual Feeling, and can never pass beyond the range of Feeling, are necessarily concerned with Matter only as the Felt.

If any one asks, What is Virtue? what is Wealth? or any other abstraction, he is satisfied when all the concrete facts are specified which the abstraction condenses in a symbol. In like manner we must be satisfied when the abstraction Matter is defined, and its concretes specified. We define it as the statical aspect of Existence, — it is whatever is, when considered as capable of acting, as Agent; the dynamical aspect of it being Force or Activity. This is the purely objective view, in which it is isolated from Feeling. On the objective view it is the Felt. If we say Matter is the generalized expression for

all things felt, the objective element in sensibles, and is logically distinguishable from Force, which is the generalized expression of all things felt in their changes, we have defined all that Experience warrants.

96. Descending to an enumeration of all the particulars included in this general definition, we specify the concrete facts of Experience, describe and classify according to their ascending degrees of complexity and dependence the various Properties and Laws disclosed by observation. Our comprehension of Matter widens with widening experiences; with more and more differentiations of Feeling arise more and more qualities in the Felt; with more and more connections among feelings arise more and more relations in the Felt; and Knowledge advances by a continuous double process of discernment of differences and classification of likenesses. Not only the positive experiences of sensibles, but the speculative inferences of extra-sensibles are grouped into a system; and thus Matter presents the twofold aspect of the Real and the Intelligible, the Felt and the Thought.

97. This task of specifying and classifying the concretes of Experience is the purpose of Science; and Metaphysics, accepting the generalized results thus reached in the several departments of research, co-ordinates them into a system. That the metaphysical system will vary with the varying materials furnished it by Science, is inevitable; and since we cannot imagine. a limit to the progressive discovery of more and more objective relations, we must be content with solutions that are but approximations. The general question, What is Matter? is answered once for all when we define Matter, the Passive Aspect of Existence. The particular questions respecting the Properties of Matter, and their mutual dependence, can only be answered by confining them to the Properties known at the time; and we must

always be prepared for fresh extensions of knowledge, as more and more of the illimitable Unknown is brought within the range of Experience.

98. If any reader is dissatisfied with this solution of the problem, let him consider whether a final solution is possible in any other case. The geometer defines his circle, and enumerates its known properties; does he suppose that there are no undiscovered properties, over which at present he is without control? Or does he feel dissatisfied with what is known, because of the unknown? Are his geometric truths uncertain, because other truths may dawn on future mathematicians? Why, then, should the physicist be dissatisfied? He has defined the known Matter, and enumerated the known properties; he has affixed definite symbols to groups of experiences, and can operate on those symbols with the certainty of their being the rational equivalents of experiences. More than this he does not need. More than this he should not ask.