The intrinsic interest of all the strange, original, dramatic and even grotesque features that they present to the historian, is in itself sufficiently great; for they possessed beliefs, institutions, and a developed mythology, which would bear comparison with anything known to antiquity in the Old World. But we have another very special and weighty reason for interesting ourselves in these religions of a demi-civilization, brusquely arrested in its development by the European invasion. To render this motive as clear as possible, allow me a supposition. Suppose, then, that by a miracle of human genius we had found means of transporting ourselves to one of the neighbouring planets, Mars or Venus for example, and had found it to be inhabited, like our earth, by intelligent beings. As soon as we had satisfied the first curiosity excited by those physical and visible novelties which the planetary differences themselves could not fail to produce, we should turn with re-awakened interest to ask a host of such questions as the following: Do these intelligent inhabitants of Mars or Venus reason and feel as we do? Have they history? Have they religion? Have they politics, arts, morals? And if it should happen that after due examination we found ourselves able to answer all these questions affirmatively, can you not imagine what interest there would be in comparing the history, politics, arts, morals and religion of these beings with our own? And if we found that the same fundamental principles, the same laws of evolution and transformation, the same internal logic, had asserted itself in Mars, in Venus and on the Earth, is it not clear that the fact would constitute a grand confirmation of our theories as to the fundamental identity of spiritual being, the conditions of its individual and collective genesis--in a word, the universal character of the laws of mind?