If one scans the history of the subject, he can readily sympathize with the reaction against science exhibited by the modern mystic in cap and gown who still answers to the name "philosopher." Formerly philosophy took all constructive thought as its province. It attracted great minds to the task of analyzing and synthesizing knowledge; and these illustrious scholars left a legacy for which we, the recipients of their bounty, may well be thankful. Then came the decay of near-eastern civilization, and the Dark Ages. With the revival of learning, philosophers became divided into two camps. One group heeded the demand of Aristotle "to trust more to observation than to speculation, and to the latter no further than it agrees with the phenomena" they dropped the ancient title and adopted that of science. The second group retained the noble old patro-nym and, disdaining all vulgar use of hand and eye, settled themselves to subjective rumination on ultimate causes. To-day the impotent residua of this clan wander through the ruins of their lost estates bewailing that nothing remains but the ghostly outlines of metaphysics, the rusty toys of epistemology, and the vestiges of an ethics which has lost all influence and prestige.

What other fate could the philosopher expect? As I have said in another essay, he yearned to be the gentleman, not the mere private secretary to Nature. He wished to evade the drudgery of the patient collector of facts, of the experimenter, of the calculator - whose wages, though sure, were small. He was enticed by the visions of wealth that speculation always promises so impudently. Consequently, he has gone bankrupt, like many another who has hoped to become rich quickly.

The philosopher, probing the universe for final causes, resents the success of his kinsman who has vulgarly engaged in trade. Under the influence of the delusion that he is grand arbiter by divine right on all intellectual problems, he tells the latter that his methods are limited in application, restricted in validity, and thus hopeless for the purpose of detecting absolute truth. Such criticisms of science cannot be refuted. They are true. But they do not have quite the consequences assumed by even their most logical proponents, and they certainly give no support to the doctrine of self-evident truth. They fail lamentably, therefore, for they are put forward chiefly as props to intuitionalism.

Let us look a little further into these questions. By making certain assumptions, any good metaphysician can prove that the earth does not exist; by making somewhat different assumptions, he can prove that it does exist, though only because man is present to perceive its existence. Now the scientist doesn't care the slightest whether the earth exists or not. He wants to know whether it is flat or round; he wants to know its constituent parts and contents; and by assuming that it does exist, he is able to do these things with some degree of satisfaction. The illustration is silly, despite the fact that solemn volumes have been written on the points involved; but it does serve to show that all formal systems of logic have the same faults, in that they must all begin with assumptions. The scientist realizes that his work has the faults of all systems in just this respect. For this reason he has long since ceased to worry about absolute truth. In his opinion absolute truth is a metaphysical term with no more meaning than abracadabra. He has come to realize that the only form of truth worth considering is what one might call man-truth. This form of verity is based upon man's belief in the time-tried doctrine of causation; it is tested by the five senses; it is sifted by experience. It is a simple scheme, that of acquiring knowledge by describing phenomena in terms with which we are familiar and of determining the relation between them; but it is the only one which has been found to be continuously and invariably serviceable.

Science makes, or endeavors to make, full use of the human faculties; and, obviously, they are the only tools at hand. But man is an imperfect creature; hence his gropings have their limitations. Unfortunately, as soon as one admits that scientific truth is relative and that the method has its limits, these admissions are stretched and distorted in a wholly illogical way. It is assumed that all findings of science have the same degree of probability - or improbability. Only too frequently science as a whole is held up to ridicule because of the discarded hypotheses of physics, chemistry, and biology. To scoff at these dead soldiers is ill mannered, for many of them did good service in the scientific advance; but to try to persuade the uncritical to believe that all scientific discoveries are similarly shortlived is criminal. For one insufficiently established theory there are thousands of facts which will never be questioned. They will stand as written, once and for all.

It is also a popular pastime, particularly among those most unfamiliar with the situation, to stake out the limits to which science admits. The sign "No trespassing here"is as familiar in the history of progressive thought as it is along the country roadside. In the past it has been placed over the estates of chemistry and physics; more recently it has been shifted surreptitiously to the domains of biology. Scientists have been told to restrain their curiosity regarding heredity and intelligence and consciousness.

Such subjects were divine mysteries. But members of the Promethean guild have never been impressed by signs. The results of their boldness are the sciences of genetics and psychology. The plain truth is that the entire universe of human experience is attackable by the scientific method; and when the last human succumbs to the freezing temperatures of this cooling sphere, he will leave solvable problems still unformulated.