[Footnote 30: This, of course, is especially liable to be the case in those children--for example in most of those technically described as "mentally deficient" and in many of those technically described as "backward"--who do not readily acquire interest in the details of a process leading to a desired end, apart from the end itself (_i. e._ in whom work does not become pleasurable for its own sake), or in those in whom there is no strong self feeling associated with the idea of successful achievement. The granting of an undue amount of assistance will, however, in its turn tend to retard or prevent the formation of these desirable mental characteristics.] [Footnote 31: There is good reason to believe that revolt against parental authority constitutes an important factor in the production of a certain class of delinquents. See _e. g._ several of the cases recorded in Healy's "Mental Conflicts and Misconduct," 1919.] CHAPTER VI ABNORMALITIES AND VARIETIES OF DEVELOPMENT--LOVE AND HATE [Sidenote: The study of the abnormal in Psychology] Up to this point, in studying the process of individual development in relation to the family environment, we have as far as possible confined our attention to the more normal aspects of this process, neglecting for the most part the many variations and aberrations to which it is liable. It is now time to explore more carefully some of the more important of these byways into which the human mind may wander in the course of its development--byways which we have hitherto passed unnoticed, or at most examined with a hasty glance, as we traced the direct path of emotional development from childhood to maturity. Some of these byways lie near to the direct path which we have already followed; others depart more widely from it, approaching near to, or sometimes definitely entering, the region of the abnormal or pathological.