What is the difference between a recept and a concept? I cannot answer this question more clearly or concisely than in the words of the writer in the _Dublin Review_ before quoted. “The difference is all the difference between seeing two things united, and seeing them _as united_.” The difference is all the difference between perceiving relations, and perceiving the relations _as related_, or between cognizing a truth, and recognizing that truth _as true_. The diving bird, which avoids a rock and fearlessly plunges into the sea, unquestionably displays a receptual knowledge of certain “things,” “relations,” and “truths;” but it does not know any of them _as such_: although it knows them, it does not _know that it knows them_: however well it knows them, it does not _think_ them, or regard the things, the relations, and the truths which it perceives as _themselves the objects of perception_. Now, over and above this merely receptual knowledge, man displays conceptual, which means that he _is_ able to do all these things that the bird cannot do: in other words, he is able to set before his mind all the recepts which he has in common with the bird, to think about them _as_ recepts, and by the mere fact, or in the very act of so doing, to convert them into concepts. Concepts, then, differ from recepts in that they are recepts which have themselves become objects of knowledge, and the condition to their taking on this important character is the presence of self-consciousness in the percipient mind.[103] I have twice stated the distinction as clearly as I am able; but, in order to do it the fullest justice, I will now render it a third time in the words of Mr. Mivart—some of whose terms I have borrowed in the above paragraph, and therefore need not now repeat. He begins by conveying the distinction as it was stated by Buffon, thus:—