nature of the subject permits; and I think I have made it evident, in the first place, that there is no such immense distinction between instinct and reason as is generally assumed—the former often being blended with the latter, and the latter as often becoming transmuted into the former,—and, in the next place, that all the higher animals manifest in various degrees the faculty of inferring. Now, _this is the faculty of reason, properly so called_; and although it is true that in no case does it attain in animal psychology to more than a rudimentary phase of development as contrasted with its prodigious growth in man, this is clearly quite another matter where the question before us is one concerning difference of kind.[7] Again, the theological distinction between men and animals may be passed over, because it rests on a dogma with which the science of psychology has no legitimate point of contact. Whether or not the conscious part of man differs from the conscious part of animals in being immortal, and whether or not the “spirit” of man differs from the “soul” of animals in other particulars of kind, dogma itself would maintain that science has no voice in either affirming or denying. For, from the nature of the case, any information of a positive kind relating to these matters can only be expected to come by way of a Revelation; and, therefore, however widely dogma and science may differ on other points, they are at least agreed upon this one—namely, if the conscious life of man differs thus from the conscious life of brutes, Christianity and Philosophy alike proclaim that only by a Gospel could its endowment of immortality have been brought to light.[8] Another distinction between the man and the brute which we often find asserted is, that the latter shows no signs of mental progress in successive generations. On this alleged distinction I may remark, first of all, that it begs the whole question of mental evolution in animals, and, therefore, is directly opposed to the whole body of facts presented in my work upon this subject. In the next place, I may remark that the alleged distinction comes with an ill grace from opponents of evolution, seeing that it depends upon a recognition of the principles of evolution in the history of mankind. But, leaving aside these considerations, I meet the alleged distinction with a plain denial of both the statements of fact on which it rests. That is to say, I deny on the one hand that mental progress from generation to generation is an invariable peculiarity of human intelligence; and, on the other hand, I deny that such progress is never found to occur in the case of animal intelligence.