theology, where even the educated people we live among can hardly be brought to see that the cause why men do hold an opinion, or practise a custom, is by no means necessarily a reason why they ought to do so. Now collections of ethnographic evidence bringing so prominently into view the agreement of immense multitudes of men as to certain traditions, beliefs, and usages, are peculiarly liable to be thus improperly used in direct defence of these institutions themselves, even old barbaric nations being polled to maintain their opinions against what are called modern ideas. As it has more than once happened to myself to find my collections of traditions and beliefs thus set up to prove their own objective truth, without proper examination of the grounds on which they were actually received, I take this occasion of remarking that the same line of argument will serve equally well to demonstrate, by the strong and wide consent of nations, that the earth is flat, and nightmare the visit of a demon.
It being shown that the details of Culture are capable of being classified in a great number of ethnographic groups of arts, beliefs, customs, and the rest, the consideration comes next how far the facts arranged in these groups are produced by evolution from one another. It need hardly be pointed out that the groups in question, though held together each by a common character, are by no means accurately defined. To take up again the natural history illustration, it may be said that they are species which tend to run widely into varieties. And when it comes to the question what relations some of these groups bear to others, it is plain that the student of the habits of mankind has a great advantage over the student of the species of plants and animals. Among naturalists it is an open question whether a theory of development from species to species is a record of transitions which actually took place, or a mere ideal scheme serviceable in the classification of species whose origin was really independent. But among ethnographers there is no such question as to the possibility of species of implements
