Bryan Magee, who has died aged 89, was hardly a typical member of the political class of the late 20th century. A polymath and a compulsive communicator, he was a bestselling author (with more than 20 books to his name), an award-winning broadcaster and “telly don”, a philosopher, authority on Richard Wagner, and for a decade an MP, for Labour and the SDP.

In 1978 he presented a 15-part series for the BBC, Men of Ideas, in which he interviewed contemporary philosophers about their work, including Isaiah Berlin, AJ Ayer, Noam Chomsky and Iris Murdoch, and won a Royal Television Society award. He followed this a decade later with The Great Philosophers (1987), also for BBC2, featuring him in conversation with major scholars about historical figures in western philosophy from Plato to Wittgenstein. Transcripts of both series were published in book form.

Magee regarded philosophy, because it tackled questions about the purpose of life, as the most important subject. He also wanted to rescue it from the excessive professionalism of academia and the barren approaches of logical positivism and linguistic analysis. His book Modern British Philosophy (1971) was based on his BBC Radio 3 series Conversations with Philosophers (1970-71); The Story of Philosophy (1998) covered the ideas of philosophers over 2,500 years; and his Confessions of a Philosopher (1997) was a successful mix of autobiography and analysis. As a popular writer on philosophy, he had a gift for making complex ideas accessible and interesting to the general reader; his many books and television programmes were never exercises in dumbing down.

Facebook Twitter Pinterest Bryan Magee was sustained by visiting appointments at various Oxbridge colleges, and universities including Harvard, Yale, London and Sydney. Photograph: Eamonn McCabe/the Guardian

His interest in ideas seemed in part a journey of self-discovery. In his 70s, he wrote two acclaimed memoirs of his childhood in Hoxton, east London; Clouds of Glory (2004) won the JR Ackerley prize for autobiography and was followed by Growing Up in a War (2007). He published a third volume, Making the Most of It, in 2018. A complicated man, he was almost solipsistic in his determination to concentrate on what interested him at the time, a trait that could strike friends as insensitive. But he was also stimulating company, delighting in gossip, others’ as well as his own.

Magee was shaped by his childhood in east London in the 1930s. During the second world war he was evacuated to rural Market Harborough in Leicestershire. When he returned, much of Hoxton had been flattened by German bombs. He had a close relationship with his father, Frederick, a man of little education but with a love of culture, who ran a clothing shop. Bryan acquired a passion for theatre and classical music from him; his mother, Sheila (nee Lynch), veered between indifference and opposition to her son’s interests. From Frederick, Bryan also absorbed a love of Wagner and leftwing political views.

Encouraged by his father, the bright cockney boy won a London county council scholarship to Christ’s Hospital in Sussex. This ancient public school transformed his life. After school he did national service with the Intelligence Corps and then went to Keble College, Oxford, where he read history, graduated with a second, and gained another with a one-year course in philosophy, politics and economics. While at Oxford he published a volume of verse, Crucifixion and Other Poems (1951), and became president of the Oxford Union in 1953. He and his peers, including William Rees-Mogg, Jeremy Thorpe and Michael Heseltine, expected to become masters of the universe.

He then took up a teaching post in Sweden, where he made a short marriage to Ingrid Söderlund, with whom he had a daughter, Gunnela. After his divorce he had several relationships but never remarried. Back at Oxford he began and abandoned a doctorate in philosophy and then spent a year on a study trip to Yale in the US. There he met and was influenced by the philosopher Susanne K Langer, who introduced him to Kant and Schopenhauer. To read the works in the original, Magee learned German, which gave him a niche in Britain, where few philosophers had studied the language.

For a period he taught philosophy at Balliol College but found linguistic philosophy, then in vogue at Oxford, too much like logic-chopping. He also objected to the requirements of teaching to a syllabus and recommending secondary reading on philosophy.

If academia was not for him, an academic base was. He was sustained for much of his life by visiting appointments at various Oxbridge colleges, and high–ranking universities including Harvard, Yale, London and Sydney. For many years he held a visiting appointment at King’s College London, specialising in the history of ideas, first as honorary senior research fellow (1984-94) and then visiting professor until 2000.

His was a life of the mind, including music and theatre, and he wrote music criticism for many publications, including the Listener, making a profession out of his hobby. Relationships were a potential distraction from his interests (“I was never prepared to sacrifice my writing”); he once said he had never fallen in love and was closer to the philosophers he studied than to his friends.

He made slow progress in his ambition to become a Labour MP. He fought the safe Conservative seat of Mid Bedfordshire in the 1959 general election and in a byelection the following year. It was another 14 years before he was returned for Leyton, north-east London, in February 1974.

Facebook Twitter Pinterest Magee was an authority on how Wagner’s music interacted with his political ideas. Photograph: Penguin

In the interim he kept busy by becoming a successful presenter on the current affairs television programme This Week, providing an earnest and progressive standpoint on topics including independence in Africa, and social issues such as prostitution, abortion and homosexuality (the last leading to a book, One in Twenty, in 1966). He also presented a TV series called Arguments (1973), in which he debated issues with leading figures. In this period he wrote an excellent short book on Karl Popper (1973), which did much to extend appreciation of Popper’s views about politics.

Neither Harold Wilson nor James Callaghan considered Magee ministerial material (his ambition was to be minister for the arts) and he continued to broadcast and write, including a novel, Facing Death (1977). He was increasingly uncomfortable as the Labour party moved left, decisively so after the 1979 general election defeat. Michael Foot’s election as party leader the following year was the last straw. Magee resigned from the party in January 1982 and within weeks joined the Social Democratic party, along with nearly 30 other Labour MPs. Standing for the SDP, he finished third in the 1983 general election.

Magee now threw himself into a life of writing about philosophy and Wagner, particularly on how his music interacted with his political ideas. His Aspects of Wagner (1968) was followed by Wagner and Philosophy (2000). Ultimate Questions (2016) was a personal meditation on the meaning of life.

He lived alone in Oxford, near Wolfson College, where he was a fellow, moving into a nursing home in his last years. He is survived by Gunnela, three grandchildren and four great-grandchildren.

• Bryan Magee, philosopher, writer and politician, born 12 April 1930; died 26 July 2019

• This article was amended on 28 July 2019. It was logical positivism, identifying factual knowledge with scientific knowledge, and not legal positivism, regarding law as an expression of authority rather than morality, that Bryan Magee wanted to rescue philosophy from.