And now will you permit me to bring forward two further considerations in support of my view. As you know, we call the doubtful and indefinable activities of earliest infancy towards pleasure ‘sexual,’ because in the course of analysing symptoms we reach them by way of material that is undeniably sexual. They would not thereby necessarily be sexual themselves, let us grant; but let us take an analogous case. Suppose that there were no way to observe the development from seed of two dicotyledonous plants—the apple-tree and the bean; but imagine that in both it was possible to follow back its development from the fully-developed plant to the first seedling with two cotyledons. The two cotyledons are indistinguishable in each; they look exactly alike in both plants. Shall I conclude from this that they actually are exactly alike and that the specific differences between apple-tree and bean-plant arise _later_ in the plant’s development? Or is it not more correct biologically to believe that this difference exists _already_ in the seedlings, although I cannot see any in the cotyledons? This is what we do when we call infantile pleasurable activities sexual. Whether each and every organ-pleasure may be called sexual or whether there exists, besides the sexual, another kind of pleasure that does not deserve this name is a matter I cannot discuss here. I know too little about organ-pleasure and its conditions; and I am not at all surprised that in consequence of the retrogressive character of analysis I arrive finally at factors which at the present time do not permit of definite classification.