Secondly, we must admit that the universal regression of the libido to the period of childhood would be inexplicable if there were nothing there which could exert an attraction for it. The fixation which we assume to exist towards specific developmental phases, conveys a meaning only if we think of it as stabilizing a definite amount of libidinous energy. Finally, I am able to remind you that here there exists a complementary relationship between the intensity and the pathogenic significance of the infantile experiences to the later ones which is similar to that studied in previous series. There are cases in which the entire causal emphasis falls upon the sexual experiences of childhood, in which these impressions take on an effect which is unmistakably traumatic and in which no other basis exists for them beyond what the average sexual constitution and its immaturity can offer. Side by side with these there are others in which the whole stress is brought to bear by the later conflicts, and the emphasis the analysis places on childhood impressions appears entirely as the work of regression. There are also extremes of "retarded development" and "regression," and between them every combination in the interaction of the two factors. These relations have a certain interest for that pedagogy which assumes as its object the prevention of neuroses by an early interference in the sexual development of the child. So long as we keep our attention fixed essentially on the infantile sexual experiences, we readily come to believe we have done everything for the prophylaxis of nervous afflictions when we have seen to it that this development is retarded, and that the child is spared this type of experience. Yet we already know that the conditions for the causation of neuroses are more complicated and cannot in general be influenced through one single factor. The strict protection in childhood loses its value because it is powerless against the constitutional factor; furthermore, it is more difficult to carry out than the educators imagine, and it brings with it two new dangers that cannot be lightly dismissed. It accomplishes too much, for it favors a degree of sexual suppression which is harmful for later years, and it sends the child into life without the power to resist the violent onset of sexual demands that must be expected during puberty. The profit, therefore, which childhood prophylaxis can yield is most dubious; it seems, indeed, that better success in the prevention of neuroses can be gained by attacking the problem through a changed attitude toward facts.