“The freeing of an individual, as he grows up, from the authority of his parents is one of the most necessary though one of the most painful results brought about by the course of his development. It is quite essential that that liberation should occur and it may be presumed that it has been to some extent achieved by everyone who has reached a normal state. Indeed, the whole progress of society rests upon the opposition between successive generations. On the other hand, there is a class of neurotics whose condition is recognizably determined by their having failed in this task.”