THEORIES OF MATERIALISM.
The doctrine of Materialism stands equally related to the "mechanical" form of Atheism, and to the "hylozoic" form of Pantheism. It is subsumed in both, and is the fundamental postulate on which they respectively depend.
It has no natural affinity with the more "ideal" or "spiritual" form of Pantheism. We must not conclude, however, that it has no historical connection with it. For it is instructive to mark, in tracing the history of philosophic speculation, that its course resembles not so much the uniform current of a stream, as the alternate flowing and ebbing of the tide; or, if we may change the figure, that its movement may be likened to the oscillation of a pendulum, which no sooner reaches its highest elevation on the one side, than it acquires a tendency to rush to the opposite extreme on the other. There can be little doubt that the recent revival of speculative "Idealism" was the result, at least in part, of a strong reaction against the "sensational" philosophy, which had degenerated in the school of Priestley at home, and in that of Condillac abroad, into a system of gross and revolting Materialism. For the same reason, we may now, I think, anticipate a speedy reaction the other way,—a reaction against the extravagances of "idealistic" and "transcendental" speculation, and a tendency towards a more practical and matter-of-fact philosophy. This tendency, if guided by the true spirit of the Baconian method, may give a powerful impulse to Inductive Science in all its departments; but, if biased by partial and one-sided views, may issue either in the temporary ascendancy of the Positive School, or the partial revival of some other form of Materialism.
Some such tendency might have been expected to arise as soon as Idealism should have reached its culminating point. For, on a comprehensive view of the whole history of speculative thought, we find that there are just four great systems of Metaphysics, which are perpetually recurring, as it were, in cycles. The first is the system of Dualism,—not the Dualism of Christian Theology, which speaks of God and nature, the Creator and the creature,—but the Dualism of ancient Paganism, which held Matter and Spirit to be equally uncreated and eternal: the second is Materialism, which resolves all into Matter and its laws: the third is Idealism, which resolves all into Mind and its modifications: and the fourth is Pantheism, which identifies Existence with Thought, and resolves all into the Absolute.[145] In the present age, Idealism is in the ascendant, and has risen to the height of Pantheism; but, by a natural reaction, many are beginning to desiderate a more substantial and practical philosophy, while the rapid progress of physical science is directing their thoughts more and more to the wonders of the material world. In these circumstances, there may be a tendency to relapse into the Materialism of the last century, which attempted to explain the whole theory of the universe by the laws of matter and motion; or at least to embrace some modification of the Positive Philosophy, which excludes all causes, whether efficient or final, from the field of human knowledge, and confines our inquiries to the mere phenomena and laws of material nature.
There are not wanting various significant indications of the existence of this tendency at the present day. It is sufficiently indicated, in some quarters, by the mere omission of all reference to Mind or Spirit as distinct from Matter; and, in others, by elaborate attempts to explain all the phenomena of life and thought by means of physical agencies and organic laws. The writings of Comte, Crousse, Cabanis, and Broussais,[146] afford ample evidence of its growing prevalence in France; and although it has been said by a recent historian of Philosophy that in England there has been no formal avowal, or at least no recognized school, of Materialism, since the publication of Dr. Thomas Brown's reply to Darwin's Zoönomia, yet there is too much reason to believe that it was all along cherished by not a few private thinkers, who had imbibed the spirit of Hobbes and Priestley; and now it is beginning to speak out, in terms too unambiguous to be misunderstood, in such works as "The Purpose of Existence" and the "Letters" of Atkinson and Martineau. But apart from the opinions of individual inquirers, it must be remembered that there is a tendency in certain studies, when exclusively pursued, to generate a frame of mind which will tempt men either to adopt the theory of Materialism, or at least to attach undue importance to physical agencies and organic laws. This tendency may be observed in the study of Physiology, especially when it is combined with that of Phrenology and Animal Magnetism; not that there is any necessary or strictly logical connection between these studies and Materialism, for some of their ablest expounders, including Cabanis, Gall, and Spurzheim, have explicitly disavowed that theory; but simply that, in prosecuting such inquiries, the mind is insensibly led to bestow an undue, if not exclusive, attention on the phenomena and laws of our material organization, so as to become comparatively unmindful of what is mental, moral, and spiritual in the constitution of man. For these reasons, and considering, especially, the close connection of Materialism both with the mechanical Atheism of the past, and the hylozoic Pantheism of the present age, we deem it necessary to subject its claims to a rigorous scrutiny, in connection with the subject of our present inquiry.
What, then, is the doctrine of Materialism? What are the forms in which it has appeared, and what the ground on which it rests? How does it stand related to the question concerning the nature and existence of God, or the constitution and destiny of Man? A brief answer to these questions will be sufficient to show that this theory cannot be safely disregarded in any attempt to construct a comprehensive and conclusive argument on the first principles of Natural Theology.