If we thus set apart for consideration under a distinct head the evolution of social organisation, the rest of the body of national traditions may be said to constitute the civilisation of a people. For the civilisation of a people at any time is essentially the sum of the moral and intellectual traditions that are living and operative among them at that particular time. We are apt in a loose way to consider the civilisation of a people to consist in its material evidences; but it is only in so far as these material evidences, the buildings, industries, arts, products, machinery, and so forth, are the expression and outcome of its mental state that they are in any degree a measure of its civilisation. We may realize this most clearly by considering the case of a people on which the material products of civilisation have been impressed from without. Thus the peasants of India live amongst, and make use of, and benefit materially by, the railways and irrigation works created by their British rulers, and are protected from invasion and from internal anarchy by the British military organisation and equipment; and they play a subordinate though essential part in the creation and maintenance of all these material evidences of civilisation. But these material evidences are not the expression of the mental state of the peoples of India, and form no true part of their civilisation; and, in fact, they affect their civilisation astonishingly little; although if these products of a higher civilisation should be maintained for a long period of time they would, no doubt, produce changes of their civilisation, probably tending in some degree to assimilate their mental state to that of Western Europe.