Albert Bandura — Canadian Psychologist born on December 04, 1925,

Albert Bandura OC is a psychologist who is the David Starr Jordan Professor Emeritus of Social Science in Psychology at Stanford University. For almost six decades, he has been responsible for contributions to the field of education and to many fields of psychology, including social cognitive theory, therapy and personality psychology, and was also influential in the transition between behaviorism and cognitive psychology. He is known as the originator of social learning theory and the theoretical construct of self-efficacy, and is also responsible for the influential 1961 Bobo doll experiment... (wikipedia)

Most of the images of reality on which we base our actions are really based on vicarious experience.
Accomplishment is socially judged by ill defined criteria so that one has to rely on others to find out how one is doing.
In order to succeed, people need a sense of self-efficacy, to struggle together with resilience to meet the inevitable obstacles and inequities of life.
Coping with the demands of everyday life would be exceedingly trying if one could arrive at solutions to problems only by actually performing possible options and suffering the consequences.
Moral justification is a powerful disengagement mechanism. Destructive conduct is made personally and socially acceptable by portraying it in the service of moral ends. This is why most appeals against violent means usually fall on deaf ears.