One such conflict, to which I have already referred when discussing the handicap of sulkiness, is conflict over sex questions. Frequently, to the parents' astonishment, it will be found that the actual cause of timidity, reticence, moodiness, or depression of spirits in a formerly happy child, is a mental conflict due to the child's vain endeavours to work out fully satisfactory answers to delicate questions which the parents have not answered when put to them by the child, or have answered in an evasive fashion. Children are far more discerning than most parents give them credit for being. Also, they often are more interested than most parents suppose in some of the fundamental problems of existence--and especially the problem of their own nature and origin. The scientific study of dreams, indeed, has furnished an additional and powerful argument against the common practice among parents of veiling in mystery or concealing with well-intentioned falsehoods the facts of birth and of sex. But let me quote, at this point, the findings of an English medical psychologist, Doctor Ernest Jones, of London, who has specially studied the reactions of children to the policy of silence and mystification regarding sex matters. "The extent to which such matters occupy the mind of the young child," says Doctor Jones, "is always underestimated by adults, and is impossible to determine by a casual examination, for, on the one hand, the later memories for these years are always deficient and erroneous, and, on the other hand, this aspect of the child's mind is rarely accessible to direct inquiry, on account of the barrier always existing on the subject between child and adult. As the child grows older, the desires and tendencies in question meet with such obstacles as an increasing sense of shame, guilt, wrongness, remorse, and so on, and are fought against by the child, who now half-consciously strives to get away from them, to forget them, or, as it is technically termed, to "repress" them. The repressed mental processes are later thus forgotten, and, along with them, a major part of the mental experiences associated with them in time. This is the reason why so little of early childhood life can be recalled by the adult. "The desires, thoughts, impulses, tendencies, and wishes thus repressed do not, however, die; they live on, but come to expression in other forms. Their energy is directed along more useful paths, a process known as "sublimation," and upon the extent and kind of this sublimation depends a great deal of the future interests and activities of the individual."[19] Under certain conditions, instead of smooth, successful sublimation, there may be mental conflict, with nervous or mental maladies as a possible result. To this undesirable outcome the parental course sometimes contributes materially. Again, I quote Doctor Jones: