Dr Richard Friedman, the psychoanalyst responsible for debunking the myth that homosexuality can be cured, has sadly passed away at the age of 79.

As a young man Friedman stood out in his field by becoming the first to combine findings in psychobiology, gender identity and family studies with psychoanalytic theory.

His revolutionary 1988 book, ‘Male Homosexuality: A Contemporary Psychoanalytic Perspective,’ showed that sexual orientation was largely biological, not mental.

It had a major impact at a time when most other psychoanalysts were continuing to describe homosexuality as a “perversion”, even though the American Psychiatric Association had stopped classifying it as an illness by 1973.

“I felt an ethical obligation to find the reasons for anti-homosexual prejudice,” he once told an interviewer, according to the New York Times.

His wife, Susan Matorin, explained his motivation more simply: “Straight people had the same personality issues, and they got away with murder, but gay people were stigmatised, and he didn’t think that was right.”

“He very much felt like you followed the science, and it didn’t matter what the political backdrop was,” his son,Jeremiah, added.

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Using studies of identical twins and theories of developmental psychology, Friedman argued that it was biology, rather than upbringing, which played a significant role in sexual orientation.

The controversial position was a direct challenge to popular Freudian theories and thrust him into the centre of debates alongside more established heavyweights of his field.

“Given that he was a younger colleague, it was brave of him to take older experts on,” Jack Drescher, a professor of psychiatry at Columbia University, told the New York Times.

Friedman went on to publish an article on female homosexuality which received an award from The Journal of The American Psychoanalytic Association as the best publication of 1998.

His work on sexuality was well ahead of its time – just last year the American Psychoanalytic Association issued a belated apology for treating homosexuality as an illness, acknowledging that its past errors contributed to discrimination and trauma for LGBT+ people.

The implications of his work continue to have an impact today as LGBT+ advocates battle against the discredited practice of conversion therapy, which is still legal in most parts of the world.

Dr Richard Friedman sadly died on March 31 at his home in Manhattan. Although his cause of death has not yet been determined, he reportedly struggled for years with health problems, including cardiac and metabolic conditions.

He is survived by a wife, son, two daughters and two grandchildren.