VI. We find repeated among animals all the phenomena which we have noticed amongst plants, and, especially in the highest orders, those movements due to unconscious irritability, of which examples are presented by plants. Some eminent men, Lamarck among the number, have even wished to refer all acts performed by inferior animals to this order of phenomena. But here the author of _La Philosophie Zoologique_ has fallen into an anatomical error, which has been long since recognised; and whoever has lived, even for a short time, by the sea-side, or has followed closely the habits and actions of worms and zoophytes will certainly protest against this manner of regarding them. Passing from the plant to the animal, the latter executes movements belonging either to the part or to the whole which are perfectly independent of the laws of gravitation and etherodynamy. The regulating and determining cause of these movements is evidently within the animal itself. It is the _Will_. But the Will itself is intimately connected with _sensibility_ and _consciousness_. To everyone who judges animals by what he finds takes place within himself, personal experiment and observation prove that the animal _feels_, _judges_, and _wills_, that is to say _reasons_, and consequently is _intelligent_. This proposition will, I know, be contested by men whose learning I profoundly respect, and objections will be made on all sides. On the one hand the Automatism of Descartes will be revived in some schools, and will now be supported by physiology and the experiments of vivisection. I am far from denying the great interest which is attached to the latter, and to the phenomena of reflex actions. But the conclusions which are drawn from them appear to me singularly exaggerated; Carpenter has rightly opposed them with personal experiment. I will add that the study of animals placed far below, and certainly inferior to, the frog, would doubtless lead to very different interpretations. Moreover, Huxley himself admits that animals are probably _sensible_ and _conscious automata_. But if they were merely machines we should be obliged to allow that they performed their functions _as if_ they felt, judged, and willed. On the other hand, in the name of philosophy and psychology, I shall be accused of confounding certain _intellectual_ attributes of the human _reason_ with the exclusively _sensitive_ faculties of animals. I shall presently endeavour to answer this criticism from the standpoint which should never be quitted by the naturalist, that, namely, of experiment and observation. I shall here confine myself to saying that, in my opinion, the animal is _intelligent_, and, although a _rudimentary_ being, its _intelligence_ is nevertheless of the _same nature_ as that of man. It is, moreover, very unequally distributed among the animal species; in this respect there are many intervening stages between the oyster and the dog.