Dr Aaron T Beck, a groundbreaking psychotherapist widely regarded as the father of cognitive therapy, died on Monday at his Philadelphia home aged 100. Beck’s work revolutionised the diagnosis and treatment of depression and other psychological disorders. He died peacefully early in the morning, according to a statement issued by the Beck Institute for Cognitive Behaviour Therapy, which he co-founded with his daughter, Dr Judith Beck. “My father was an amazing person who dedicated his life to helping others,” his daughter said, noting that her father continued to work right up to his death. “He has inspired students, clinicians, and researchers for several generations with his passion and his groundbreaking work.” Beck developed the field of cognitive behavioural therapy, a clinical form of psychotherapy, at the University of Pennsylvania in the 1960s. It prompts patients to focus on distortions in their day-to-day thinking, rather than on conflicts buried in childhood. He developed the treatment after finding that his depressed patients frequently experienced distorted negative ideas – he dubbed them “automatic thoughts”. Unlike Freudian psychoanalysis, which delves into a patient’s childhood and searches for hidden internal conflicts, cognitive therapy says turning around a self-disparaging inner monologue is key to alleviating many psychological problems. He touted the idea with an anti-Freudian maxim: “There’s more to the surface than meets the eye.” Beck discovered that patients who learn to recognise the faulty logic of their negative automatic thoughts – such as, “I’ll always be a failure” or “no one likes me” – could learn to overcome their fears and think more rationally, which diminished their anxiety and improved their mood. He found that results endured long after therapy was finished, as patients learned to confront those thoughts on their own. Cognitive therapy sessions follow a strict format, which always include setting goals for the session and homework assignments. Besides depression, it has been used to treat conditions including bulimia, panic attacks, social phobia, obsessive-compulsive disorder and drug abuse. Beck’s pragmatic view of psychotherapy had its sceptics. Some psychologists called cognitive therapy superficial and little more than a morale booster, but it became required training for psychiatry residents. Beck always responded to critics with data from his research. He published much of his work in his own journal, Cognitive Therapy and Research, partly because other mental health professionals disregarded his findings. He wrote or co-wrote 17 books, published more than 500 articles and received honours for his work including the Albert Lasker Award for Clinical Medical Research in 2006, the Heinz Award for the Human Condition in 2001, and the Sarnat Award from the Institute of Medicine. American Psychologist magazine in 1982 named Beck one of the 10 most influential psychotherapists ever. A native of Providence, Rhode Island, and the third son of middle-class Russian Jewish immigrants, Beck’s first exercises in cognitive therapy were on himself, after a childhood hospitalisation at eight. The athletic child and Boy Scout became fearful of hospitals and blood, and the smell of ether could make him faint. He said he overcame those fears by learning to disregard his wooziness and keep busy with other activities. As a young psychologist, he conducted experiments disproving the Freudian theory that people were depressed because they somehow needed to suffer. He concluded that depression didn’t come from masochism, as Freud believed, but from low self-worth. In 2005 and 2014, he engaged in public and private dialogues with the Dalai Lama. They concluded that CBT and Buddhism have much in common. Beck is survived by his wife of more than 70 years, former state Judge Phyllis Beck, along with three other children, 10 grandchildren and 10 great-grandchildren.