Animal psychology is not only justified as a science, but we can even hope that correct observations of animal intelligence will assist us in correctly understanding the higher intelligence of human thought. And “that some useful hints may be taken from watching children is not denied” by Prof. Max Müller either, although this little concession appears only in the shape of a short foot-note. The _homo alalus_ is by no means a merely mythical figure, for according to the law of evolution man must have developed out of a being lower than the present man. His first ancestor must have been simple life-substance something like that of the amœba. He must have passed through a long period in which he was not capable of articulate speech. That we know nothing particular about the _homo alalus_ is no proof against his existence. Moreover every infant is an actual real _homo alalus_, a speechless man, or should we according to Prof. Max Müller class our babies among the brutes? Prof. Max Müller says (_The Monist_, p. 585): “If, like Professor Romanes, we begin with the ‘immense presumption that there has been no interruption in the developmental process in the course of psychological history,’ the protest of language counts for nothing; the very fact that no animal has ever formed a language, is put aside simply as an unfortunate accident.” The theory of evolution rightly understood is no presumption in the usual sense of the word. It is no more a presumption than to say that something cannot come from nothing. And what is “the protest of language” which would disprove the continuity of evolution? That rational or human thought is something _sui generis_, that it is different in kind and not in degree from brute intelligence; that language is an impassable barrier between man and brute, being the Rubicon which no other animal has crossed. Very well. We agree entirely with all these propositions. Human reason is different in kind from brute intelligence and human reason has developed such as it is through language only. Nay reason is language. Noiré is right when he says, Man thinks because he speaks. But the Rubicon of language was not an absolutely impassable barrier. The speechless ancestor of man, whether we call him _homo alalus_ or anthropoid, or even man-ape, _has_ crossed it, and having crossed it he became the Cæsar of the animal creation.