Adolescence represents an inner emotional upheaval, a struggle between the eternal human wish to cling to the past and the equally powerful wish to get on with the future.
The toddler must say no in order to find out who she is. The adolescent says no to assert who she is not.
Adolescence is the conjugator of childhood and adulthood.
Children, even infants, are capable of sympathy. But only after adolescence are we capable of compassion.