In order to demonstrate the effect of the development of the Ego upon the tendency to conflict and therewith upon the causation of the neurosis, I will quote an example which, although entirely imaginary, is not at all improbable in any respect. I will give it the title of Nestroy’s farce: _On the Ground-Floor and in the Mansion_. Suppose that a caretaker is living on the ground-floor of a house, while the owner, a rich and well-connected man, lives above. They both have children, and we will assume that the owner’s little girl is permitted to play freely without supervision with the child of lower social standing. It may then very easily happen that their games become “naughty,” that is, take on a sexual character: that they play “father and mother,” watch each other in the performance of intimate acts, and stimulate each other’s genital parts. The caretaker’s daughter may have played the temptress in this, since in spite of her five or six years she has been able to learn a great deal about sexual matters. These occurrences, even though they are only kept up for a short period, will be enough to rouse certain sexual excitations in both children which will come to expression in the practice of masturbation for a few years, after the games have been discontinued. There is common ground so far, but the final result will be very different in the two children. The caretaker’s daughter will continue masturbation, perhaps up to the onset of menstruation, and then give it up without difficulty; a few years later will find a lover, perhaps bear a child; choose this or that path in life, perhaps become a popular actress and end as an aristocrat. Probably her career will turn out less brilliantly, but in any case she will be unharmed by the premature sexual activity, free from neurosis, and able to live her life. Very different is the result in the other child. She will very soon, while yet a child, acquire a sense of having done wrong; after a fairly short time she will give up the masturbatory satisfaction, though perhaps only with a tremendous struggle, but will nevertheless retain an inner feeling of subdued depression. When later on as a young girl she comes to learn something of sexual intercourse, she will turn from it with inexplicable horror and wish to remain ignorant. Probably she will then again suffer a fresh irresistible impulse to masturbation about which she will not dare to unburden herself to anyone. When the time comes for a man to choose her as a wife the neurosis will break out and cheat her out of marriage and the joy of life. If analysis makes it possible to obtain an insight into this neurosis, it will be found that this well-broughtup, intelligent and idealistic girl has completely repressed her sexual desires; but that they are, unconsciously, attached to the few little experiences she had with the childish play-mate.