The following is another chapter of the revised Medico-Moral Problems book of Father Gerald Kelly, S.J., being published by The Catholic Hospital Association. Permission has been granted to give this preview of material concerning psychosurgery. Many of the book\u27s chapters begin with a quotation of directives which are observed in the operation of Catholic hospitals, included in the publication, Ethical and Religious Directives for Catholic Hospitals. Directive 44 which is the basis for Father Kelly\u27s considerations of the treatment of mental illness and pain provides the introduction to his discussion