“But the whole of their understanding stops at that point. The understanding they possess is not one that can consider itself: it cannot see itself, does not know itself. They do not possess _reflection_, that supreme faculty with which the mind of man is endowed, and which enables him to turn his intellectual power inwards, so as to study and know the nature of his own understanding. “Reflection, thus defined, is then the boundary that separates human intelligence from that of the brute creation: and in fact it cannot be denied that this furnishes a strong line of demarcation between them. Thought, which contemplates itself; understanding, which sees itself and studies itself; knowledge, which knows itself; these evidently constitute an order of determinate phenomena of a decided character, and to which no brute animal can ever attain. This is, if one might so speak, a purely intellectual domain; and it appertains to man alone. In one word, animals feel, know, think; but man is the only one of all created beings to whom has been given the power of feeling that he feels, of knowing that he knows, and of thinking that he thinks.”[188] I will quote, also, the following passage from my work sur _l’instinct et l’intelligence des animaux_, p. 178, et seq. “ ... There are three facts: _instinct_, _understanding of brutes_, and _human understanding_; and each of these facts has its definite limits. “Instinct acts without knowing; understanding knows in order to act; the human understanding alone knows, and knows itself. “Reflection, closely defined, is the _knowledge of thought by thought_. And this power of thought over thought gives us a whole order of new relations. As soon as the mind perceives itself it judges itself; as soon as it can act upon itself it is free; as soon as it becomes free it becomes moral. “Man is only moral because he is free. “The brute animal follows its body; in the midst of this body, which shrouds it completely in matter, the human mind is free, and so free that it can, whenever it prefers to do so, immolate its very body. “‘The great power of the will over the body,’ says Bossuet, ‘consists in this prodigious effect, that man is so completely master of his frame, that he can even sacrifice it for the sake of some greater good in view. To rush into the midst of blows, and plunge into a flight of arrows from a blind impetuosity, as happens among brute creatures, shows nothing superior to the body itself; but to resolve to die with understanding, and for reasons, notwithstanding the whole disposition of the body to the contrary, evinces a principle superior to the body; and among all the tribes of animals, man is the only one in whom this principle exists.’” NOTE III. GALL, AS AN OBSERVER. Page 93. _He studied them (mankind) in his own way, but he studied them very closely._