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On the Method of Mr. Darwin in his Treatise on the Origin of Species.

By H. Fawcett, M.A.

He said that, as he could not conform to what he believed was the rule, that communications should be read (Mr. Fawcett being blind), he would promise to keep as close to his subject as though he had written his paper. The title which he originally fixed upon was, "That the method of investigation pursued by Mr. Darwin, in his Treatise on the Origin of Species, is in strict accordance with the principles of logic." He feared that he might be charged with presumption in attempting to say anything on Mr. Darwin's great work, which had already engaged the attention of the most accomplished naturalists of the day. He had been

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assured that the discussion on the subject at the last Meeting of the Association had never been surpassed in the interest it excited or in the talent which it called forth. Indeed, the work had divided the scientific world into two great sections; Darwinite and anti-Darwinite were almost the badges of opposite parties. Professor Owen, Professor Sedgwick, and Mr. Hopkins had given to the new theory a decided opposition; Sir Charles Lyell, Professor Huxley, and Dr. Hooker had given to it a support more or less decided. All who took an interest in the subject had a right to inquire whether the theory—whatever might be thought of its details—had been logically brought forward. The province of logic was not to discover new facts, but to decide whether facts were legitimately used to establish that which it was pretended they proved. It was constantly alleged that Mr. Darwin was illogical; that he had not followed the Baconian method. The 'Quarterly Review' assured us that Mr. Darwin had not followed in the steps of Newton and of Kepler; but nothing was more easy than to make such charges, which often only concealed pretentious assumptions of scientific knowledge. It was more pertinent to inquire— What is the method of solution of which such a problem admits? He insisted that if ever solved it could only be by a method analogous to that attempted by Mr. Darwin. It could only be solved in this way: —An hypothesis, resting upon more or less perfect induction, must be started; from that hypothesis certain deductions must be drawn; these deductions must be tried, by seeing whether they would explain the phenomena of nature, and they must be verified by seeing whether they agreed with what can be observed in nature. If this explanation and verification was complete, the hypothesis was adyanced from an unproved to the position of a proved and established theory. The Bishop of Oxford last year said that the theory was so absurd that no scientific man could for a moment think that it was in any degree worth considering, But Dr. Hooker, than whom a more eminent authority could not be quoted, at once disposed of the Bishop by saying, that as he believed the theory worth considering, he ought to "apologise for addressing the meeting as a man of no scientific authority." Dr. Hooker added that he knew of the theory five years before; that, at first, no one more opposed it; but five years' devotion to natural history had convinced him that the theory was worthy of the most careful consideration and examination. Mr. Darwin, with the most perfect candour, explained in his work that his theory did not yet explain all the facts of nature; but it must not be supposed that his twenty years' labour had done nothing to advance the ends of science. Mr. Darwin had strictly followed the rules of the deductive method as laid down by John Stewart Mill. When Kepler inferred his law of the connexion between the major axis of the planets and the times of their revolution, he so inferred from observation, which he could strictly verify by mathematical calculation.

The origin of species does not admit of such a verification. In chemistry there was much more power of proof or verification by experiment than was possible in physiology; so with other sciences. When laws of nature cannot be discovered by experiment, we are obliged to go to deductive reasoning. Newton had only an hypothesis, and not a theory, as to the law of gravitation; the law he first tried was an incorrect one. He tried again; and then, as Professor Whewell said, by a tentative process he discovered the correct law. Mr. Darwin had told him (the speaker) that his hypothesis was not at once suggested to him. He found in his studies that there was something wanted to explain many of the observed phenomena; years passed, and at length his hypothesis was very indirectly suggested— for he said that it came from reading Malthus's 'Essay on Population." Twenty years of unremitting labour he had devoted to the endeavour to verify the conclusions which might be deduced from this hypothesis by the facts observable in nature. He believed that Mr. Darwin's second work, for which the author had accumulated a great mass of knowledge, would prove beyond doubt that no one could have been a more conscientious or laborious observer than he had been. Newton could verify his hypothesis by the simplest experiment—he had but to drop a stone from a tower and to note the time occupied in its descent. But the problem of the origin of species is concerned with an epoch of time associated with geological epochs; therefore experiment could only be made during so short a time, that nothing more could be obtained than an argument resting on a, comparatively speaking, unsatisfactory analogy. Darwin had been able to show that by a system of artificial natural selec-

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tion two organisms, originally descending from the same form, could be made to differ so much, that if they were found as fossils they would undoubtedly be classed as distinct species; and, therefore, how a morphological species could be produced. But his experiments had failed to show how a physiological species could be produced; for no one could show that two varieties from the same form could be made to differ so much that they would possess the quality of infertility. This was too often forgotten by objectors. The Egyptian sculptures were pointed to to prove that during 3000 years the causes looked to by Darwin had done nothing to alter the form of animals. But what would be said to him who, by discovering that 3000 years ago Mont Blanc was of the same altitude as now, should think that he had thus disposed of the theories of modern geology, that the stupendous peaks of Switzerland were lifted from their ocean bed, and that every change on the surface of the earth had been produced by an indefinite continuation of physical causes which are in ceaseless operation? Mr. Darwin admitted that geology did not show that in animal life there had been those transitional links that ought to exist according to his theory, and according to any other of gradual transmutation. He (the author) could not see that this theory detracted one iota from any of the attributes of the Creator. If we suppose that the introduction of every new species required a distinctive act of creative will, then, of course, the Creator must have interposed every time a new species was introduced. But, if we supposed that every living organism has descended from those forms in which life was first placed upon this planet, it does not in the slightest source dispense with the necessity of supposing that life could only first be so placed by the act of Omnipotent Creative Will. It was a favourite illustration in religious works, the discovery of Newton which explains how planetary motions are produced; and he (Mr. Fawcett) believed that if ever the day came when the origin of species should be explained in fulness and simplicity, he who so explained it would be considered not only to have advanced science, but to have conferred a benefit upon religion. The attackers of Darwin forget that he has not attempted to displace a theory received as right, but merely to throw some light where all before was dark. We should therefore, be all the more ready to welcome the conscientious labours of one who like Mr. Darwin had unremittingly devoted himself to explain to some extent what had been aptly termed the "mystery of mysteries."