Dinner with Father Cyril Barrett — and you would dine well with this accomplished cook, even if in somewhat chaotic surroundings — was an intellectual feast composed of unpredictable ingredients. A man of huge charm, voracious curiosity and lively humour, he made an open house of his great learning. It was a place that offered inspiration and discovery to those who stepped across its threshold, at the University of Warwick where he taught philosophy for nearly three decades, in Dublin and London, or on his adventurous travels on a Jesuitical shoestring. (Holy Ghost Airlines, he would joke about the dodgier charter flights to dodgy destinations.) As an experimental new university in the mid-Sixties, Warwick attracted, and was attracted by, his interdisciplinary and questing cast of mind. Barrett was as authoritative on Op Art as he was on Wittgenstein’s aesthetics.

Inducted almost straight from school into the Society of Jesus but, wisely, given free rein to pursue his strong academic vocation, Cyril Barrett found his reference points as writer, critic and lecturer in philosophy, aesthetics and a lifelong engagement with religious meaning; but he branched outward in multiple directions. He could discourse as intriguingly on hot racing tips, the samizdat blue films circulating in Cold War Central Europe (about which he was alarmingly well informed), kitsch or even knitting, as he talked about medieval aesthetics, Kierkegaard or Picasso. The most unclerical of priests, his faith was deep yet never unquestioning, just as the intellect that made him a renowned philosopher and art critic was tempered by the intensity of his inner spiritual dialogue.

Denis Cyril Barrett was born in 1925 in Dublin, to the sort of horse-and-hounds family that throws up, as it did with his great-uncle Cyril Corbally, such eccentric luminaries as champion croquet players. But this was independence-era Dublin, with its charged politics. His father Denis, the last Assistant Commissioner of the pre-1922 Dublin Metropolitan Police and the first of the Garda Siochana that replaced it, was to resign out of disgust with de Valera’s brand of nationalism and the virulence of the IRA — a disgust always shared by his son. His mother died when he was three, and he was brought up by his adored stepmother Evelyn.

His early trajectory was conventional, from Ampleforth to a first in History and Latin at University College, Dublin, and thence to licenciates both in philosophy and in theology before ordination. How little these disciplines were to confine him was demonstrated by his doctorate, on symbolism in the arts, and a subsequent year studying anthropology and the role of myth at University College, London and the Warburg Institute. His large body of books and essays was to be almost equally devoted to modern art — where his influence was enormous and Europe-wide — and to philosophical studies.

As a philosopher, Barrett became celebrated for publishing, in 1966, a selection of student notes of Wittgenstein’s lectures and conversations on aesthetics, psychology and religious belief — a small corpus out of which has developed a massive secondary literature and which has profoundly influenced aesthetics and theology. All his formidable persuasive skills were put to the test in gaining the consent of the notoriously possessive executors; Wittgenstein declared that “only aesthetic and conceptual questions” really gripped him, but without the Barrett enterprise, few would have known for many years of his grapplings with the former, or indeed with religion.

A quarter of a century later he gave his own considered account of Wittgenstein on ethics and religious belief, arguing that his views on value developed but did not change. Wittgenstein, he maintained, held that seeking to inculcate moral principles, and teaching religion in propositional form, is contrary to the true nature of ethics and religious belief — a position he endorsed. But he resisted the influential misinterpretation according to which Wittgenstein held religious belief to be nothing more than a way of life according to a picture. Belief is involved. The “picture” of Judgment Day is more than a mere picture or exemplar; it is a picture to live by, and there are better and worse such pictures; Wittgenstein “was no more a relativist than any reasonable person can avoid being”.

While never a Wittgensteinian, and indeed characteristically hostile to the notion of philosophical discipleship, he certainly learnt from him, and in aesthetics this influence came out in at least two ways. First, in his preference for tackling particular problems and clarifying ideas, over constructing elaborate theories, and secondly in his engagement with the interconnections between aesthetics and psychology, expressed most notably in his pioneering work popularising and explaining Op Art, both in books and by organising exhibitions. As an art critic he was wide-ranging and formidable — his catalogue of 19th-century Irish Victorian Art is a classic of its kind — but also creative. He was a driving force in establishing Warwick University’s art collection, and in cultivating understanding of modern art in Ireland. “Are bad works of art ‘works of art’?” , he asked in an influential essay; his suitably nuanced answer was that they may well be.

Jesuits, avowedly and by direction, are deeply involved in the world’s affairs — and the greatest of them are mavericks. To someone of Barrett’s catholic interests, impatience of convention and detestation of intellectual narrowness, Catholicism can be a hard master. Like many Jesuits down the centuries, Barrett made no attempt to disguise his chafing at the Vatican’s hierarchical politics and social conservatism — going so far as to declare on the day of the attempted assassination of the Pope, in a bellow that filled a London restaurant, that “the only thing wrong with that bloody Turk was that he couldn’t shoot straight”.The religious affairs correspondent of The Sunday Times, seated at a nearby table, turned beetroot.

Yet Barrett could readily assume his priestly guise and, in that capacity, was a compassionate and subtle counsellor and eminently practical moralist, ultimately convinced of the intelligence as well as the goodness of the Holy Spirit and able to instil that belief in others.

Academic politics bored Barrett at least as much as the priestly variety, and the world of league tables, research assessments and other bureaucratic rigidities even more. He left Warwick in 1992 for Campion Hall, Oxford, with some relief, striding into the Bodleian and demanding (successfully) to use the Latin language procedure for registering for a reader’s ticket.

He continued writing to the very end of his life, back in Dublin, and was working in the last weeks on books and articles ranging from the morality of war to the limits of science, as well as writing poetry and rewriting the Spiritual Exercises of St Ignatius. Barrett would, however, have described this as the pursuit of leisure, which for him was “not a trivial pursuit”, and nothing to do with idleness, but, rather, “life lived to its fullest” .

Work was necessary for survival, he wrote, but “It is not an end in itself. Leisure is. It is the end, the goal, of human life, the proper state of man” — which is why the quality of leisure matters. There are echoes here of Aristotle, even of St Augustine’s idea of entering the holy Sabbath of God. But Cyril Barrett’s genius was to draw the classical forward into the present; to cite one of his aphorisms, “philosophy may be perennial, but it is not static”.

Cyril Barrett, SJ, Jesuit priest and former Reader in Philosophy at the University of Warwick, was born on May 9, 1925. He died of cancer on December 30, 2003, aged 78.