Sexuality from a psychological point books field of psychology has extensively studied homosexuality as a human sexual orientation. The American Psychiatric Association listed homosexuality in the DSM-I inbut almost immediately that classification came under scrutiny in research funded by the National Institute of Mental Health. That research and subsequent studies consistently failed to produce any empirical or scientific basis for regarding homosexuality as anything other than a natural and normal sexual orientation that is a healthy and positive expression of human sexuality.
Upon a thorough review of the scientific data, the American Psychological Association followed in and also called on all mental health professionals to take the lead in "removing the stigma of mental illness that has long been associated" with homosexuality. Inthe National Association of Social Workers adopted the same position as the American Psychiatric Association and the American Psychological Association, in recognition of scientific evidence.
The longstanding consensus of scientific research and clinical literature demonstrate that same-sex sexual and romantic attractions, feelings, and behaviors are normal and positive variations of human sexuality.
The view of homosexuality as a psychological disorder has been seen in literature since research on homosexuality first began; however, psychology as a discipline has evolved over the years in its position on homosexuality. Current attitudes have their roots in religious, legal, and cultural underpinnings. Some Ancient Near Eastern communities, such as the Israeliteshad strict codes forbidding homosexual activity, and this gave way to later usage of the same texts by the original missionaries of Christianitywho themselves descended from the tribes of Israel ; Paul in particular is notable for his allusion to and reinforcement of such texts Sexuality from a psychological point books his letters to nascent churches.
Later, the Apostolic Fathers and their successors continued to speak against homosexual activity whenever they mentioned it in their surviving writings. In the early Middle Ages the Christian Church ignored homosexuality in secular society; however, Sexuality from a psychological point books the end of the 12th century, hostility towards homosexuality began to emerge and spread through Europe's secular and religious institutions.
There were official expressions condemning the "unnatural" nature of homosexual behavior in the works of Thomas Aquinas and others. Until the 19th century, Sexuality from a psychological point books activity was referred to as "unnatural, crimes against nature", sodomy or buggery and was punishable by law, sometimes by death. In the beginning of the 19th century, people began studying homosexuality scientifically.
At this time, most theories regarded homosexuality as a disease, which had a great influence on how it was viewed culturally. Psychiatrists began to believe homosexuality could be cured through therapy and freedom of self, and other theories about the genetic and hormonal origin of homosexuality were becoming accepted. There were variations of how homosexuality was viewed as pathological.
Freud and Ellis believed that homosexuality was not normal, but was "unavoidable" for some people. Alfred Kinsey 's research and publications about homosexuality began the social and cultural shift away from viewing homosexuality as an abnormal condition. These shifting viewpoints in the psychological studies of homosexuality are evident in its placement in the first version of the Diagnostic Statistical Manual DSM inand subsequent change inin which the diagnosis of ego-dystonic homosexuality replaced the DSM-II category of "sexual orientation disturbance".
Sigmund Freud's views on homosexuality were complex. In his attempts to understand the causes and development of homosexuality, he first explained bisexuality as an "original libido endowment",  by which he meant that all humans are born bisexual.
He believed that the libido has a homosexual portion and a heterosexual portion, and through the course of development one wins out over the other. He also believed in a basic biological explanation for natural bisexuality in which humans are all biologically capable of being aroused by either sex.
Because of this, he described homosexuality as one of many sexual options available to people. "Sexuality from a psychological point books" proposed that humans' inherent bisexuality leads individuals to eventually choose which expression of sexuality is more gratifying, but because of cultural taboos homosexuality is repressed in many people.
According to Freud, if there were no taboos people would choose whichever was more gratifying to them — and this could remain fluid throughout life — sometimes a person would be homosexual, sometimes heterosexual. Some other causes of homosexuality for which he advocated included an inverted Oedipus complex where individuals begin to identify with their mother and take themselves as a love object.