At school at Shrewsbury and at university at Balliol College, Oxford, he got his expected First in Greats in 1953. A convert to Roman Catholicism in his student days, he then began training for the secular priesthood in England and subsequently in Rome. But in 1955 he came to see his vocation as lying within the Benedictine Order, and he became a novice at Downside Abbey. A year later, however, polio struck with full force and the monastic life was no longer a possibility for him.
So, studying mostly at his parental home at Midsomer Norton near Bristol, he wrote an Oxford doctoral thesis in Philosophy; and he then began his career as a professional philosopher, becoming an Assistant Lecturer at Hull University in 1962.
Christopher Williams was an only child, and much of the practical assistance involved in caring for him and transporting him was provided, especially at the early stages of his career, by his devoted parents. But the move to Hull marked the beginning of greater independence. Hull University, though small and none too wealthy, equipped a bedroom for him in a hall of residence with apparatus to lift him in and out of bed; and students and colleagues readily lifted him in and out of his specially adapted car and pushed him round the campus.
At Hull and subsequently volunteers for this work were never hard to find - because Williams had charm. Students and colleagues wanted to push him along corridors and help him into his car, because he was so agreeable - interesting, amusing and yet charitable. Some volunteers were regulars; they knew the exact place to hold the wheelchair in order to lift him upstairs, or where to push in order to get the chair on to a pavement. But, often, there was an unfamiliar outsider, a passer-by summoned by Williams to help with just one lift, and Williams patiently explained for the millionth time just what his helper should do.
Although very independent at Hull, Williams was pleased to have the opportunity to move back to Bristol in 1965; this enabled him to live again at his parental home, from which he drove regularly the 15 miles into Bristol three times a week. He was Lecturer and then Reader at Bristol University; and finally was awarded a personal professorship in Philosophy in 1989.
As well as his many articles in philosophical journals, Williams's main contributions to philosophy consisted of books in two areas - ancient and medieval philosophy; and philosophical logic. He translated and edited an edition of Aristotle's De Generatione et Corruptione in 1982; and transcribed, translated and edited the treatise of Paul of Venice, De Necessitate et Contingentia Futurorum, in 1991. On the philosophical logic side he wrote three books, What is Truth? (1976), What is Existence? (1981), What is Identity? (1989); and produced a simple version of all three within the covers of one book, Being, Identity and Truth (1992). Inspired by Frege and Wittgenstein, and more directly by Arthur Prior and Peter Geach, he analysed carefully the nature of these very general concepts - defending and elaborating for example the view that existence is a second-order concept; that to say that God exists is not, strictly speaking, to say something about God but to say something about the concept of God, that there is an instance of that concept.
For five years he was editor of the influential philosophical journal Analysis. He was a regular attender of philosophical conferences (where colleagues took over from machines to get him in and out of bed). He taught for a semester in America - at Notre Dame University. He lectured in Poland. He visited France annually for many years, staying at the Abbey at Bec (where Anselm, who raised powerfully with his ontological argument the issue of the nature of the concept of existence, was once Abbot); he holidayed in Russia. But illness began to creep up on him; and he just managed to keep his teaching going until his retirement in 1996. He was in the process of finishing an edition and translation of Philoponus's commentary on De Generatione et Corruptione, when a cardiac arrest hastened his death.
A devout Catholic, he maintained his connection with Downside Abbey throughout his life.
Christopher John Fardo Williams, philosopher: born Walsall 31 December 1930; Assistant Lecturer in Philosophy, Hull University 1962-65; Lecturer in Philosophy, Bristol University 1965-72, Reader 1972-89, Professor of Philosophy 1989-96; died Bristol 25 March 1997.