The work of Rocha Filho is representative of the high level of psychiatric, psychoanalytic and social interpretation developed in recent years by South American workers. His contributions have comprised special studies in schizophrenia; psychiatry in relation to mental hygiene and social and public health problems; and crime and delinquency. The present work is a collection of essays along these lines, popularly presented, forming the second title in a series of works by Alagoan authors the scope of which is to include studies in different fields.