Social and Ethical Interpretations in Mental Development
THE main consideration which this paper  aims to present, that of the responsibility of. all men, be they great or be they small, to the same standards of social judgment, and to the same philosophical treatment, is illustrated in the very man to whose genius we owe the principle upon which my remarks are based—Charles Darwin; and it is singularly appropriate that we should also find the history of this very principle, that of variations with the correlative principle of selection, furnishing a capital illustration of our inferences. Darwin was, with the single exception of Aristotle, possibly the man with the sanest judgment that the human mind has ever brought to the investigation of Nature. He represented, in an exceedingly adequate way, the progress of scientific method up to his day. He was disciplined in all the natural science of his Predecessors. His judgment was an epitome of the scientific in sight of the ages which culminated then. The time was ripe for such
(567) a great constructive thought as his—ripe, that is, as far as the accumulation of scientific data was concerned. His judgment differed then from the judgment of his scientific contemporaries mainly in that it was sounder and safer than theirs. And with it Darwin was a great constructive thinker. He had the intellectual strength which put the judgment of his time to the strain—everybody's but his own. This is seen in the fact that Darwin was not the first to speculate in the line of his great discovery, nor to reach formulas; but with the others guessing took the place of induction. The formula was an uncriticised thought. The unwillingness of society to embrace the hypothesis was justified by the same lack of evidence which prevented the thinkers themselves from giving it proof. And if no Darwin had appeared, the problem of biological development would have been left about where it had been left by the speculation of the Greek mind. Darwin reached his conclusion by what that other great scientific genius in England, Newton, described as the essential of discovery, 'patient thought'; and having reached it, he had no alternative but to judge it true and pronounce it to the world.
But the principle of variations with natural selection had the reception which shows that good judgment may rise higher than the level of its own social origin. Even yet the principle of Darwin is but a spreading ferment in many spheres of human thought in which it is destined to bring the same revolution that it has worked in the sciences of organic life. It was not until other men, who had both authority with the public and sufficient information to follow Darwin's thought, seconded his judgment, that his great formula began to have currency in scientific circles.
The passage referred to in Professor Poulton's Charles Darwin and the Theory of Natural Selection (Macmillans, 1896, pp. 12 f.) is so fully in accord with the position of my text that I allow myself to quote it entire: —
" It is a common error to suppose that the intellectual powers which make the poet or historian are essentially different from those which make the man of science. Powers of observation, however acute, could never make a scientific discoverer; for discovery requires the creative effort of the imagination. The scientific man does not stumble upon new facts or conclusions by accident; he finds what he looks for. The problem before him is essentially similar to that of the historian who tries to create an accurate and complete picture of an epoch out of
(569) scattered records of contemporary impressions more or less true, and none wholly true. Fertility of imagination is absolutely essential for that step from the less to the more perfectly known, which we call discovery.
"But fertility of imagination alone is insufficient for the highest achievements in poetry, history, or science; for in all these subjects the strictest self-criticism and the soundest judgment are necessary in order to insure that the results are an advance in the direction of the truth. . . .
" It is probable then that the secret of Darwin's strength lay in the perfect balance between his powers of imagination and those of accurate observation, the creative efforts of the one being ever subjected to the most relentless criticism by the employment of the other. ' We shall never know,' I have heard Professor Michael Foster say, ' the countless hypotheses which passed through the mind of Darwin, and which, however wild and improbable, were tested by an appeal to nature, and were then dismissed forever.'
"Darwin's estimate of his own powers is given with characteristic candour and modesty in the concluding paragraph of his Autobiography (Life and Letters, 1887, p. 107) : -
" 'Therefore my success as a man of science, whatever this may have amounted to, has been determined, as far as I can judge, by complex and diversified mental qualities and conditions. Of these the most important have been—the love of science,—unbounded patience in long reflecting over any subject,—industry in observing and collecting facts, — and a fair share of invention as well as of common sense. With such moderate abilities as I possess, it is truly surprising that I should have influenced to a considerable extent the belief of scientific men on some important points."'