Peter Lipton - an internationally distinguished scholar, an inspired teacher practising what one former student has called "the pedagogy of exuberance", and a model of clarity and character - has died suddenly after a heart attack, aged 53. He was the first Hans Rausing professor of the history and philosophy of science, head of the department of history and philosophy of science, and a fellow of King's College, Cambridge. He was also co-chair of the Beth Shalom reform synagogue in Cambridge and an intellectual light in the world of progressive Judaism.
Born in New York to German Jews who had fled the Nazis, he found his commitment to living an ethical life was encouraged by the Ethical Culture Fieldston school, from which he went on to read physics and philosophy at Wesleyan University, Connecticut. He then studied at New College, Oxford, where he earned his BPhil in 1978 and his DPhil in 1985 with a thesis on explanation and evidence under AJ Ayer, and met his wife Diana. From 1985 to 1990 he was assistant professor at Williams College in Massachusetts, where their two sons were born. He joined the Cambridge department of history and philosophy of science in 1991, becoming holder of the departmental chair in 1997. He was head of department from June 1996 until his death.
The department flourished under his skilled and shrewd leadership, bringing together the sometimes competing intellectual frameworks of the history and philosophy of science, fuelled by the espresso coffee machine he was proud of having installed. He was equally respected and admired in the wider university for his constructive energy and insight, most recently becoming chair of the library syndicate. He was also a valued fellow of King's, where he tirelessly encouraged intellectual interaction between students and fellows.
Lipton loved to discuss the ideas that animated him - among them the problems of induction, other minds, and testimony - with people of every age and intellectual ability. Thus, he chose to stage his brilliant inaugural lecture in March 1998 as a contribution to the university's science week to a vast audience, many of them children. He announced that the lecture was designed so that 12-year-olds could understand it, though their parents might have some difficulty. He taught by example that part of respecting another person is taking the time to criticise his or her views. At the end of a 1999 lecture course, his students showered him with red roses as a mark of celebration and gratitude. He spent much time bringing philosophy to the wider world by visiting schools and sixth-form colleges, and wrote 253 responses to the askphilosophers.org website, responding to one inquirer that while "reading [the philosophical questions on the site] might just make you more aware, thinking about them just might make you more intelligent".
Lipton's most important contribution to the philosophy of science and epistemology is his book Inference to the Best Explanation (1991, second edition 2004). This work has become a standard text on the theory of explanation, according to which, when we try to explain something, we make an inference from the available evidence. Lipton wrote widely, too, on topics concerning the philosophy of mind, freedom of the will, laws of nature, and bioethics. He chaired a working party on ethical issues of pharmacogenetics as a member of the Nuffield council on bioethics, producing the report Pharmacogenetics: Ethical Issues in 2003, and was a fellow of the Academy of Medical Sciences. In 2004 he was Medawar prize lecturer at the Royal Society.
As a self-described "religious atheist" - believing strongly in the value of Jewish identity and community in his own life - he was increasingly preoccupied with the question of the epistemological status of religion, exploring this theme in sermons and academic articles alike. Against critics claiming that religion is false, unnecessary and harmful, he argued that one could be justified in living and thinking in religious terms without having to believe in every entity those terms might posit; that while religion was not necessary to be moral, it could still be a valuable resource and support for that endeavour; and that its harm or benefit depended on the intellectual and moral responsibility with which it was pursued.
A colleague recalls that even knowing Lipton professionally, it was clear "that love was at the centre of his life". In lectures he would criticise theories if they were shallow in rendering the experience of love. He loved philosophy, jokes, squash and, above all, his family. The Shabbat dinners that he and Diana hosted, welcoming academic visitors and unexpected cross-sections of the academic and Jewish communities to which they belonged, were legendary.
He is survived by Diana, sons Jacob and Jonah, and his mother Lini.
· Peter Lipton, philosopher of science, born October 9 1954; died November 25 2007
