Many-sided development of human has belonged to the humanistic ideas o
f the philosophy since the Ancient (Classical) Ages; it is important f
or education and consultancy, for mental hygiene, as well as for the i
mprovement of the labour power mobility; theoretically, from the viewp
oint of the personality structure and development. Members of the Depa
rtment of Psychology at the Faculty of Arts, Charles University in Pra
gue, in cooperation with numerous graduands and graduates, have studie
d this problem since the sixties. From the psychological point of view
, they define the many-sidedness - one-sidedness - undevelopment of th
e personality by means of combining data about activities, personality
subsystems, motivation, and development of the individual. The one-si
dedness of the personality is also expressed by means of marginal area
s of the polar personality traits, while the middle zone of traits cor
responds to the many-sidedness of the development The many-sided - one
-sided development of activities, especially at the age of 11-19 years
, was studied, too. Several forms of many-sidedness - one-sidedness -
undevelopment in adolescents and grown-up persons was differentiated.
From among the conditions in operation, especially the following one w
ere studied: socio-cultural conditions of the family,important others
off the family, groups and hobby-groups, common activities, way of edu
cation within the family, activity of the individual, passivity of the
individual, changes in the way of life in mature age. Unfavourable co
nditions are, in many cases, more or less compensated by other conditi
ons, external ones, but mainly by the individual's activity, his/her e
ffort aimed at self-determination. The compensating, and - on the othe
r hand - disturbing operation was expressed by means of the personalit
y development conception in branches that diverge or converge accordin
g to the complementary conditions.