It is not surprising that the book Force and Matter (1855)—in the preface to which these sentiments are expressed—went through sixteen editions in thirty years and was translated into most European languages. It is an extreme expression of the most thorough-going materialism, and the circumstance that its conclusions were acceptable neither to cautious scientists nor to critical philosophers, did not compromise its authority with the general public. As was only natural, for materialism is a creed for which the evidence is all on the surface, and to which the objections, being less obvious, escape notice. And Büchner's pleas for intelligibility and clearness, though in some sense justified by the inconceivable pedantry of much German metaphysics, was, in point of fact, only a form of cant; for "there are difficulties lying in the subject-matter itself which cannot be banished from the sphere of philosophy." Appeals to popular prejudices are not a more legitimate form of philosophic, than of scientific controversy; serious thinkers do not thus stoop to the expedients of the politician.
Effects of Darwin's Theory.—It would be a serious mistake, then, to imagine that materialistic naturalism had to wait for the publication of the Origin of Species (1859) before it could become a formidable theory. And yet the appearance of Darwin's book had important effects, and among these is to be reckoned a certain weakening of the old "Argument from Design," according to which the complexity and delicacy evident everywhere in the world of nature, could not be attributed to chance, but pointed to the existence and activity of a divine Designer. Paley, during the eighteenth century, had elaborated the argument with a wealth of detailed instances of "contrivance":
"The pivot upon which the head turns, the ligament within the socket of the hip-joint, the pulley or trochlear muscles of the eye; the epiglottis, the bandages which tie down the tendons of the wrist and instep," and so on.
And it was not so much the doubt cast by it upon the separate creation of particular species that was the disturbing element in Darwin's hypothesis (few men now regarded the book of Genesis as a manual of natural science, or faith in it, as such, as a matter of religious obligation); it was rather that the new doctrine of "natural selection" seemed to invalidate the "argument from design." Design or chance had been the alternatives offered by Paley, and chance only had to be mentioned to be rejected; but Darwin made it possible to escape from the dilemma. He showed how, if certain conditions were granted, the whole process of the manufacture of species would naturally and inevitably follow. Neither design nor chance was the explanation: there was another alternative, the influence of environment. Thus Paley's instances of elaborate "contrivance" were explained by Darwin as instances of adaptation. The environment under which these organs had developed had made them what they were; they could not, under the given circumstances, have been different. As a very lucid writer puts it:
"Before Darwin's great discovery, those who denied the existence of a Contriver were hard put to it to explain the appearance of contrivance. Darwin, within certain limits and on certain suppositions, provided an explanation. He showed how the most complicated and purposeful organs, if only they were useful to the species, might gradually arise out of random variations, continuously weeded by an unthinking process of elimination."[41]
Darwinism Exploited.—In fact, it became evident that popular materialism had been strongly reinforced by the new biology; and though Darwin himself was cautious in adding philosophic or religious corollaries to his own propositions, some of his more eager disciples did not hesitate to fill in his blanks, and to draw conclusions which the master was too conservative, too blind, or perhaps too scientific to sanction.
The distinguished zoologist Haeckel (1834-1919) may be reckoned the most notable amongst these. He was one of the first German scientists to give his adherence to Darwin, who seems to have considered him too zealous a disciple. "Your boldness sometimes makes me tremble," he wrote (November 19, 1868). It is not every scientist who can perceive the limits of an hypothesis, or who insists so conscientiously as Darwin did, upon the necessity for its verification.
Herbert Spencer.—Though there were not wanting in England writers to exploit Darwinian theories in the interests of a narrow secularism, their work was not of first-rate importance, and need not detain us. A new evolutionary philosophy was, however, worked out by a conscientious thinker of a different calibre—Mr. Herbert Spencer. He indeed may be described as the Aristotle of a new world-view. He attempted to co-ordinate and unify all human knowledge, and to present the world with a final philosophy based upon the data supplied by natural science. To this ambitious task he devoted a lifetime of patient work, broken by intervals of ill-health. In 1850 the System of Synthetic Philosophy was projected; its First Principles were published in 1862, but it was not until 1896 that the gigantic enterprise was complete.
Spencer was inspired neither by hostility to religion in general, nor to Christianity in particular. The motive of his work was a more honourable one. He felt, with many of his contemporaries, that the foundations of the old religion were no longer secure, and that the old sanctions of morality were already gravely compromised; and he wished to supply a new creed and a new discipline in the place of these. His principal objects were social and ethical. And in this important respect he may be associated with Comte. Both were sociologists and moralists before they were philosophers, which accounts for their overlooking and underestimating various important philosophic difficulties.
A few remarks about Spencer's system are here not out of place. He attempted to reduce experience to a unity by seeking evidence for the existence of a single and universal law. This unifying principle he found in a general law of evolution. He formulated this law in language which is perhaps less obscure than it seems, and which practically amounts to this, that there is a perpetual process going on which reduces disorder to order, undifferentiated sameness to specialised variety.[42]