anatomy; and I found that of all the senses, the eye was the most superficial; the ear, the proudest; smell, the most voluptuous; taste, the most superstitious and the most inconstant; touch, the profoundest and the most of a philosopher.  It would be amusing to get together a society, each member of which should have no more than one sense; there can be no doubt that they would all treat one another as out of their wits.”

This is interesting, because it was said at the time to be the source of one of the most famous fancies in the philosophical literature of the century, the Statue in Condillac’s Treatise on the Sensations.  Condillac imagined a statue organised like a man, but each sense unfolding itself singly, at the will of an eternal arbiter.  The philosopher first admits the exercise of smell to his Frankenstein, and enumerates the mental faculties which might be expected to be set in operation under the changing impressions made upon that one sense.  The other senses are imparted to it in turn, one by one, each adding a new group of ideas to the previous stock, until at length the mental equipment is complete.

We may see the extent of the resemblance between Condillac’s Statue and Diderot’s muet de convention, but Diderot at least is free from the charge of borrowing.  Condillac’s book was published three years (1754) after the Letter on the Deaf and Dumb, and he afterwards wrote a pamphlet defending himself from the charge of having taken the fancy of his Statue from Diderot; nor, for that matter, did Diderot ever make sign or claim in the matter.  We have already spoken of the relations between the two philosophers, and though it is a mistake to describe Diderot as one of Condillac’s most celebrated pupils,[77] yet there is just as little reason to invert the connection, or to doubt Condillac’s own assertion that the Statue was suggested to him by Mademoiselle Ferrand, that remarkable woman to whose stimulating and directing influence he always professed such deep obligation.  Attention has been called to the fact that in 1671 a Parisian bookseller published a Latin version of a much more intelligent and scientific fancy than the Statue—­the Philosophus Autodidactus of the Arabian, Ibn Tophail.  This was a romance, in which a human being is suckled by a gazelle on a desert island in the tropics, and grows up in the manner of some Robinson Crusoe with a turn for psychological speculation, and gradually becomes conscious, through observation, of the peculiar properties belonging to his senses.[78]

Of the part of the Letter that concerns gesture, one can only say that it appears astonishingly crude to those who know the progress that has been made since Diderot’s time in collecting and generalising the curious groups of fact connected with gesture-language.  We can imagine the eager interest that Diderot would have had in such curious observations as that gesture-language has something like a definite syntax; that it furnishes