Many of those who look at these problems from (what they deem to be) a strictly scientific point of view are not likely to be more favourable. Their loyalty to experience takes the form of supposing that men accumulate knowledge by peering about for “sequences” among “phenomena,” as a child looks for shells upon the beach—equally ready to go north or south, east or west, as the humour of the moment moves him. They would regard any antecedent preference for this or that sort of explanation as a sin against the categorical imperatives of intellectual morals. Science, they think, should have no partialities: and as the honest investigator “entertains no belief with a conviction the least in excess of the evidence,”[12] so he will resist any leaning toward one kind of conclusion rather than another. Such is their view of scientific duty. Scientific practice, however, has been otherwise. That the practice of ordinary humanity has been otherwise seems indeed sufficiently plain. The folk-lore, the magic, and the religions of primitive races, with all their unborrowed resemblances, are there to attest it. But these (you will say) are superstitions. The objection is not, I think, relevant; yet, for the sake of peace, let us pass to what is not regarded as a superstition, namely, morality. Here you have the singular spectacle of a close agreement among moralists as to the contents of the moral law, and a profound disagreement as to the grounds on which the moral law is to be accepted. Can the power of “tendency” be better shown? Can there be a clearer illustration of the way in which it may guide belief and anticipate proof? II But our business to-day is neither with magic nor morality. It is with physical science. When we survey man’s strivings to understand the world in which he lives, can we detect any secular leanings towards certain types of belief, any deep-lying inclination to guess by preference in one direction rather than another? We surely can. There are some answers, for example, which we refuse to take from experiment and observation. I have already referred to one such case in connection with causation. No man of science can be provoked, by any seeming irregularities, into supposing that the course of nature is subject to lapses from the rule of perfect uniformity. Consider, again, another case, where the tendency is far less strong, but where few can doubt that it is real. I refer to the deep-seated reluctance felt by most physicists to accept as final any scientific explanation which involves a belief in “action at a distance”—a reluctance which is the more remarkable since action at a distance seems a familiar fact of experience, while action by contact, when you attempt to work it out in detail, seems hard to comprehend.