upon questions of origin and agency and purpose; devoted, in short, to physical philosophy. The problem of the true relation subsisting between irrational and rational nature is the problem of the day. An endeavour then will here be made to elucidate what are the lessons taught us by a combined study of nature in its two aspects, rational and irrational.
It is probable that the last quarter of a century has, in Speculative England, seen a more quickly growing and more wide-spread crop of speculative questioning than any former period of like duration. More than this, it is doubtful whether any period of the world's past history has witnessed a more general uncertainty, not only respecting the solution of particular problems, but as to the possibility of satisfactorily and certainly answering any one of them.
Thus it has come about that from increased speculative activity, and the inability of physical science to satisfy the questions raised, men devoted to physical science have been forced into philosophy. "Metaphysics," which had become (especially in this country) a byword of reproach, are again avowedly pursued. A reaction has set in, and the importance of philosophy, indeed its absolute necessity as a basis for science, is made manifest by the most popular teachers of physical knowledge. On the Continent, Buchner, Vogt, Hartmann, and Strauss have powerfully aided in directing popular attention to philosophical problems. In England, in spite of the oft-repeated assertions of the unprogressiveness of metaphysics, and the comparisons drawn between the efforts of metaphysicians and those of Sisyphus, our bookshelves teem with evidence that devotion to philosophy is on the increase amongst us, and physicists such as Carpenter, Bence Jones, Bastian, Huxley, Tyndall, Darwin, Wallace, with many more, have all, in various degrees, wandered beyond the domain which is specially their own into the metaphysical region. Even that annual national congress, which was instituted expressly for the promotion of physical science, had its session of 1872 inaugurated by an address on "the mental processes by which are formed those fundamental