Theorization by Peter Blos
It was the psychoanalyst Peter Blos (1904–1997) who first defined adolescence as a distinct phase of life, characterized by unique psychological dynamics and developmental demands—a crucial stage for every individual, as it allows for the formation of identity. This process is what the psychoanalyst calls the “second individuation process” (the first individuation occurs at the end of the early Oedipal phase, between the ages of 5 and 6, and was conceptualized by Sigmund Freud).
In the 1960s, Blos outlined six phases and subphases of adolescence, coining terms that are now commonly used in our everyday language:
– Preadolescence phase (ages 11–13)
– Adolescence phase (ages 13–18)
– First subphase of adolescence (ages 13–15)
– Second subphase of adolescence (ages 15–18)
– Late adolescence phase (ages 18–20)
– Post-adolescence phase (which leads the individual into adulthood)
Special attention and care—both from parents and from society as a whole—must be devoted to this developmental phase, as unresolved issues during adolescence can impact an individual’s entire life. It is undoubtedly a challenging task, especially in our time.

