That sounds very like religious belief controlling a man's philosophy. Just such an example in a woman's philosophy is given by Mary Geach in an introduction to a collection of essays, Faith in a Hard Ground (2008) by the renowned philosopher G E M Anscombe, her mother.  Elizabeth Anscombe had come across a passage in Bertrand Russell to the effect that an argument from the facts of the world to the existence of God could not be valid "as one could not deduce a necessary conclusion from a contingent premiss". She could not at the time see what was wrong with Russell's principle, but "she had known that to deny the possibility of moving by reason from the facts of the world to a knowledge of the existence of God was to deny a doctrine defined as of faith by an ecumenical council".  Elizabeth Anscombe's response to this dilemma, her daughter relates, was to go to church and make an act of faith. Later she realised that Russell was wrong and "of course one can derive necessary conclusions from contingent premises". Mary Geach commented: "If she had relied on her own understanding, she would have lost her faith for a falsehood."  The doctrine referred to here must be one laid down by the First Vatican Council in 1870. The one true God, our Lord and creator, it said, can be known by the natural light of human reason through created things. Most people do not lie awake worrying about the consequences of such a claim, but most people are not philosophers.  As it happens, this seems the very problem that, by his own account, compelled Sir Anthony Kenny, before he became Master of Balliol, to embrace agnosticism and to leave the Catholic priesthood. In an interview with Cardinal Heenan in 1963 he explained "how as a student I had been dissatisfied with the accounts given in the textbooks of how we know that there is a God, and that faith seemed to be a sacrifice of integrity rather than a virtue", he wrote in A Path from Rome (1985).  Later in the same book he says that "having rejected the Catholic discipline which insisted that the existence of God was provable no matter what fallacies I might discover in the arguments offered", he could, more dispassionately "examine the proofs of the existence of God to see whether any of them was valid".  He looked at the "Five Ways" of Thomas Aquinas sketched in the Summa Theologiae, and satisfied himself none was valid. Later, in A Life in Oxford (1997), he reflects "perhaps I should have made a closer study of the Summa Contra Gentes; or perhaps I should have looked to philosophers other than Aquinas".  Even in rejecting the Five Ways, Sir Anthony made some observations that might usefully engage the brains of a more doctrinaire kind of atheist, for example, in his treatment of the argument from design. He had more to say about this in his book Reason and Religion (1986), and in a recent interview remarked that "the argument from design seems to be quite strong in pointing to the need for some extra-cosmic intelligence". That does not sound quite like "God, our Lord" but it is not easy to think who else it is.
Which comes first, faith or philosophical proof? Christopher Howse on the    latest twist in the controversy.