Formation of self-identity is the period where children make their own standards of thoughts. It is the period where they make efforts a lot to perceive
necessary information for their own standards of thoughts; they practice self-actualization by these standards of thoughts formed in this period as they
live as adults whose ages are over 20. Based on adapting methods formed in adaptation to relationships, children make their own standards of thoughts
of human relationships in this period of forming self-identity.
In case of sons in formation of self-identity, their thoughts depend on their moods; their standards of thoughts are based on right or wrong. So, they have
positive feelings when certain information fits their standards and negative feelings when it doesn’t fit their standards. These negative feelings operate as stress;
positive feelings give fun and interest. Therefore, sons who are males feel that their psychology is stabilized and that they are happy when they feel fun and
interest in these positive moods, but they think their psychology is unstable and feel unhappy when they get stress from negative moods.
On the other hand, in case of daughters in formation of self-identity, their thoughts depend on their emotions; their standards of thoughts are based on likes
or dislikes. So, they have positive emotions when certain information fits their standards and negative emotions when it doesn’t fit their standards. Negative
emotions operate as wounds; positive emotions operate as love and emotions of happiness. Therefore, daughters who are females feel their psychology is stable
and think that they are happy when they feel love and emotion of happiness from positive emotions, but they feel unhappy and think their psychology is
unstable when they feel wounds from negative emotions.
Like this, in the period of forming self-identity, children make their own standards of thoughts. It is the process of making standards through right or wrong
and through likes or dislikes. It is the process where children experience trials and errors a lot.