And yet so well aware were they that this method was an improvement on their own that, when they could trust each other not to tell, they would surreptitiously use it.  These same Dyaks, it may be added, are, according to Mr. A.R.  Wallace, the best of observers, “among the most pleasing of savages.”  They are good-natured, mild, and by no means bloodthirsty in the ordinary relations of life.  Yet they are well known to be addicted to the horrid practice of head-hunting.  “It was a custom,” Mr. Wallace explains, “and as a custom was observed, but it did not imply any extraordinary barbarism or moral delinquency.”

The drawback, then, to a reign of pure custom is this:  Meaningless injunctions abound, since the value of a traditional practice does not depend on its consequences, but simply on the fact that it is the practice; and this element of irrationality is enough to perplex, till it utterly confounds, the mind capable of rising above routine and reflecting on the true aims and ends of the social life.  How to break through “the cake of custom,” as Bagehot has called it, is the hardest lesson that humanity has ever had to learn.  Customs have often been broken up by the clashing of different societies; but in that case they merely crystallize again into new shapes.  But to break through custom by the sheer force of reflection, and so to make rational progress possible, was the intellectual feat of one people, the ancient Greeks; and it is at least highly doubtful if, without their leadership, a progressive civilization would have existed to-day.

It may be added in parenthesis that customs may linger on indefinitely, after losing, through one cause or another, their place amongst the vital interests of the community.  They are, or at any rate seem, harmless; their function is spent.  Hence, whilst perhaps the humbler folk still take them more or less seriously, the leaders of society are not at pains to suppress them.  Nor would they always find it easy to do so.  Something of the primeval man lurks in us all; and these “survivals,” as they are termed by the anthropologist, may often in large part correspond to impulses that are by no means dead in us, but rather sleep; and are hence liable to be reawakened, if the environment happens to supply the appropriate stimulus.  Witness the fact that survivals, especially when the whirligig of social change brings the uneducated temporarily to the fore, have a way of blossoming forth into revivals; and the state may in consequence have to undergo something equivalent to an operation for appendicitis.  The study of so-called survivals, therefore, is a most important branch of anthropology, which cannot unfortunately in this hasty sketch be given its due.  It would seem to coincide with the central interest of what is known as folk-lore.  Folk-lore, however, tends to broaden out till it becomes almost indistinguishable from general anthropology.  There are at least two reasons for this.  Firstly, the survivals of