Psychology
Psychology is the science of behavior and mind, including conscious and unconscious phenomena, as well as feeling and thought. It is an academic discipline of immense scope and diverse interests that, when taken together, seek an understanding of the emergent properties of brains, and all the variety of epiphenomena they manifest. As a social science it aims to understand individuals and groups by establishing general principles and researching specific cases.
Violence
Violence is defined by the World Health Organization as "the intentional use of physical force or power, threatened or actual, against oneself, another person, or against a group or community, which either results in or has a high likelihood of resulting in injury, death, psychological harm, maldevelopment, or deprivation," although the group acknowledges that the inclusion of "the use of power" in its definition expands on the conventional understanding of the word. This definition involves intentionality with the committing of the act itself, irrespective of the outcome it produces. However, generally, anything that is excited in an injurious or damaging way may be described as violent even if not meant to be violence (by a person and against a person).
Psychology
The Savage interrupted him. "But isn't it natural to feel there's a God?"
"You might as well ask if it's natural to do up one's trousers with zippers," said the Controller sarcastically. "You remind me of another of those old fellows called Bradley. He defined philosophy as the finding of bad reason for what one believes by instinct. As if one believed anything by instinct! One believes things because one has been conditioned to believe them. Finding bad reasons for what one believes for other bad reasons–that's philosophy. People believe in God because they've been conditioned to.
"But all the same," insisted the Savage, "it is natural to believe in God when you're alone–quite alone, in the night, thinking about death …"
"But people never are alone now," said Mustapha Mond. "We make them hate solitude; and we arrange their lives so that it's almost impossible for them ever to have it."
Aldous Huxley, Brave New World, chapter 17
Psychology
Psychology appeared to be a jungle of confusing, conflicting, and arbitrary concepts. These pre-scientific theories doubtless contained insights which still surpass in refinement those depended upon by psychiatrists or psychologists today. But who knows, among the many brilliant ideas offered, which are the true ones? Some will claim that the statements of one theorist are correct, but others will favour the views of another. Then there is no objective way of sorting out the truth except through scientific research.
Raymond Cattell (1965). The Scientific Analysis of Personality, Baltimore, MD: Penguin, p. 14.