Antony Flew, the son of a Methodist minister, was born in London, England. He was educated at St Faith's School, Cambridge followed by Kingswood School, Bath. During the Second World War he studied Japanese at the School of Oriental and African Studies, University of London, and was a Royal Air Force intelligence officer. After a period with the Inter-Services Topographical Department in Oxford, he was posted to Bletchley Park in June 1944.

After the war, Flew achieved a first class degree in Literae Humaniores at St John's College, Oxford. Flew was a graduate student of Gilbert Ryle, prominent in ordinary language philosophy. Both Flew and Ryle were among many Oxford philosophers fiercely criticised in Ernest Gellner's book Words and Things (1959). A 1954 debate with Michael Dummett over backward causation was an early highlight in Flew's career.

For a year, Flew was a Lecturer in Philosophy at Christ Church, Oxford. Afterwards, he was a lecturer for four years at the University of Aberdeen, and a Professor of Philosophy at the University of Keele for twenty years. Between 1973 and 1983 he was Professor of Philosophy at the University of Reading. At this time, he developed one of his most famous arguments, the No true Scotsman fallacy in his 1975 book, Thinking About Thinking. Upon his retirement, Flew took up a half-time post for a few years at York University, Toronto.

Flew married on 28 June 1952. He had two daughters. Flew died on 8 April 2010.

Prominent atheist

While an undergraduate, Flew attended the weekly meetings of C. S. Lewis's Socratic Club fairly regularly. Although he found Lewis to be "an eminently reasonable man" and "by far the most powerful of Christian apologists for the sixty or more years following his founding of that club," he was not persuaded by Lewis's argument from morality as found in Mere Christianity. Flew also criticised several of the other philosophical proofs for God's existence. He concluded that the ontological argument in particular failed because it is based on the premise that the concept of Being can be derived from the concept of Goodness. Only the scientific forms of the teleological argument ultimately impressed Flew as decisive.

During the time of his involvement in the Socratic Club, Flew also wrote the article "Theology and Falsification," which argued that claims about God were meaningless where they could not be tested for truth or falsehood. Though initially published in an undergraduate journal, the article came to be widely reprinted and discussed. Later, in God and Philosophy (1966) and The Presumption of Atheism (1976, reprinted 1984), Flew argued that one should presuppose atheism until evidence of a God surfaces. Flew was also critical of the idea of life after death and the free will defence to the problem of evil.

Revised views

Conversion from atheism

On several occasions, apparently starting in 2001, rumours circulated claiming that Flew had converted from atheism. Flew denied these rumours on the Secular Web website.

In January 2003 Flew and Gary Habermas, his friend and philosophical adversary, conducted a dialogue on the resurrection at California Polytechnic State University - San Luis Obispo. During a couple of telephone discussions shortly after that dialogue, Flew explained to Habermas that he was considering becoming a theist. While Flew did not change his position at that time (he signed the Humanist Manifesto III), he concluded that certain philosophical and scientific considerations were causing him to do some serious rethinking. He characterised his position as that of atheism standing in tension with several huge question marks.

In December 2004, an interview with Flew conducted by Gary Habermas was published in the journal Philosophia Christi (published by the Evangelical Philosophical Society with the assistance of Biola University), with the title, Atheist Becomes Theist - Exclusive Interview with Former Atheist Antony Flew. Flew agreed to this title. According to the introduction, Flew informed Habermas in January 2004 that he had become a deist, and the interview took place shortly thereafter. Then the text was amended by both participants over the following months prior to publication. In the article Flew states that he has left his long-standing espousal of atheism by endorsing a deism of the sort that Thomas Jefferson advocated ("While reason, mainly in the form of arguments to design, assures us that there is a God, there is no room either for any supernatural revelation of that God or for any transactions between that God and individual human beings."). Flew stated that "the most impressive arguments for God’s existence are those that are supported by recent scientific discoveries" and that "the argument to Intelligent Design is enormously stronger than it was when I first met it". He also answered in the affirmative to Habermas's question, "So of the major theistic arguments, such as the cosmological, teleological, moral, and ontological, the only really impressive ones that you take to be decisive are the scientific forms of teleology?". He supported the idea of an Aristotelian God with "the characteristics of power and also intelligence", stating that the evidence for it was stronger than ever before. He rejects the ideas of an afterlife, of God as the source of good (he explicitly states that God has created "a lot of" evil), and of the resurrection of Jesus as a historical fact though he has allowed a short chapter arguing for Christ's resurrection to be added into his latest book.

Flew is particularly hostile to Islam, and says it is "best described in a Marxian way as the uniting and justifying ideology of Arab imperialism." In a December 2004 interview he said: "I'm thinking of a God very different from the God of the Christian and far and away from the God of Islam, because both are depicted as omnipotent Oriental despots, cosmic Saddam Husseins".

Controversy over his position

Flew subsequently changed his position given in the Habermas interview as justification for his endorsing of deism. In October 2004 (before the December publication of the Flew-Habermas interview), a letter written to Richard Carrier of the Secular Web, stated that he was a deist and also said that "I think we need here a fundamental distinction between the God of Aristotle or Spinoza and the Gods of the Christian and the Islamic Revelations." Flew also said: "My one and only piece of relevant evidence [for an Aristotelian God] is the apparent impossibility of providing a naturalistic theory of the origin from DNA of the first reproducing species ... [In fact] the only reason which I have for beginning to think of believing in a First Cause god is the impossibility of providing a naturalistic account of the origin of the first reproducing organisms."

In another letter to Carrier of 29 December 2004 Flew went on to retract his statement, writing "a deity or a 'super-intelligence' [is] the only good explanation for the origin of life and the complexity of nature", and "I now realise that I have made a fool of myself by believing that there were no presentable theories of the development of inanimate matter up to the first living creature capable of reproduction". He blamed his error on being "misled" by Richard Dawkins, claiming Dawkins "has never been reported as referring to any promising work on the production of a theory of the development of living matter". His 2007 book revisited the question, however, and questioned contemporary models: "the latest work I have seen shows that the present physical universe gives too little time for these theories of abiogenesis to get the job done." He added: "The philosophical question that has not been answered in origin-of-life studies is this: How can a universe of mindless matter produce beings with intrinsic ends, self-replication capabilities, and "coded chemistry"? Here we are not dealing with biology, but an entirely different category of problem."

The work of physicist Gerald Schroeder had been influential in Flew's new belief, but Flew told Carrier that he had not read any of the critiques of Schroeder that Carrier referred him to.

However, in spring 2005, when Raymond Bradley, an atheist in Editorial Board for The Open Society journal, wrote an open letter to Flew accusing him of not "check[ing]the veracity of [Schroeder's] claims before swallowing them whole", Flew strongly responded to that charge in a letter published in the same journal in summer 2006, describing the content of Bradley's letter "extraordinary offensive" and the accusation made by him as an "egregiously offensive charge"; he also implied that Bradley was a "secularist bigot", and suggested that he should follow Socrates's advice (as scripted in Plato's Republic) of "follow[ing] the argument wherever it leads".

When asked in December 2004 by Duncan Crary of Humanist Network News if he still stood by the argument presented in The Presumption of Atheism, Flew replied he did but he also restated his position as deist: "I'm quite happy to believe in an inoffensive inactive god". When asked by Crary whether or not he has kept up with the most recent science and theology, he responded with "Certainly not", stating that there is simply too much to keep up with. Flew also denied that there was any truth to the rumours of 2001 and 2003 that he had converted to Christianity.

Restatement of position

A letter on Darwinism and theology which Flew published in the August/September 2004 issue of Philosophy Now magazine left the world hanging when it closed with, "Anyone who should happen to want to know what I myself now believe will have to wait until the publication, promised for early 2005, by Prometheus of Amherst, NY of the final edition of my God and Philosophy with a new introduction of it as ‘an historical relic’."

The preface of God and Philosophy states that the publisher and Flew went through a total of four versions (each extensively peer-reviewed) before coming up with one that satisfied them both. The introduction raises ten matters that came about since the original 1966 edition. Flew states that any book to follow God and Philosophy will have to take into account these ideas when considering the philosophical case for the existence of God:

1. A novel definition of "God" by Richard Swinburne
2. The case for the existence of the Christian God by Swinburne in the book Is There a God?
3. The Church of England's change in doctrine on the eternal punishment of Hell
4. The question of whether there was only one big bang and if time began with it
5. The question of multiple universes
6. The fine-tuning argument
7. The question of whether there is a naturalistic account for the development of living matter from non-living matter
8. The question of whether there is a naturalistic account for non-reproducing living matter developing into a living creature capable of reproduction
9. The concept of an Intelligent Orderer as explained in the book The Wonder of the World: A Journey from Modern Science to the Mind of God by Roy Abraham Varghese
10. An extension of an Aristotelian/Deist concept of God that can be reached through natural theology, which was developed by David Conway.

In an interview with Joan Bakewell for BBC Radio 4 in March 2005, Flew rejected the fine-tuning argument as a conclusive proof: "I don't think it proves anything but that it is entirely reasonable for people who already have a belief in a creating God to regard this as confirming evidence. And it's a point of argument which I think is very important - to see that what is reasonable for people to do in the face of new evidence depends on what they previously had good reason to believe." He also said it appeared that there had been progress made regarding the naturalistic origins of DNA. However, he restated his deism, with the usual provisos that his God is not the God of any of the revealed religions. In the same interview, Flew was asked whether he was retracting belief in an Aristotelian God, but answered no.

One month later, Flew told Christianity Today that although he was not on the road to becoming a Christian convert, he reaffirmed his deism: "Since the beginning of my philosophical life I have followed the policy of Plato's Socrates: We must follow the argument wherever it leads."

In late 2006, Flew joined 11 other academics in urging the British government to teach intelligent design in the state schools.

In 2007, in an interview with Benjamin Wiker, Flew said again that his deism was the result of his "growing empathy with the insight of Einstein and other noted scientists that there had to be an Intelligence behind the integrated complexity of the physical Universe" and "my own insight that the integrated complexity of life itself — which is far more complex than the physical Universe — can only be explained in terms of an Intelligent Source." He also restated that he was not a Christian theist.

Book with Varghese

In 2007, Flew published a book titled There is a God, which was listed as having Roy Abraham Varghese as its co-author. Shortly after the book was released, the New York Times published an article by religious historian Mark Oppenheimer, who stated that Varghese had been almost entirely responsible for writing the book, and that Flew was in a serious state of mental decline, having great difficulty remembering key figures, ideas, and events relating to the debate covered in the book. His book praises several philosophers (like Brian Leftow, John Leslie and Paul Davies), but Flew failed to remember their work during Oppenheimer's interview. The article provoked a public outcry, in which atheist PZ Myers called Varghese "a contemptible manipulator."

A further article by Anthony Gottlieb noted a strong difference in style between the passages giving Flew's biography, and those laying out the case for a god, with the latter including Americanisms such as "beverages", "vacation" and "candy". He came to the same conclusion as Oppenheimer, and stated that "Far from strengthening the case for the existence of God, [the book] rather weakens the case for the existence of Antony Flew". Varghese replied with a letter disputing this view. Flew released a statement through his publisher stating that although Varghese did the actual writing, the book belonged to him and represented his thinking. An audio commentary by William Lane Craig Dr. Craig's Current Events Audio Blog - RFMedia.org concurs with this position, but Richard Carrier disputes this view. In June 2008, Flew stated his position once again, in a letter to a fellow of the Universities and Colleges Christian Fellowship.

Christian writer Regis Nicoll claims that "Moreover, in a signed, handwritten letter (a copy of which I now have) sent to Roy Varghese, the legendary philosopher reaffirmed his conversion while criticising Oppenheimer for drawing attention away from the book’s central argument: the collapse of rationalism." From UnChristian to Christian He argues that "Even Mark Oppenheimer described the ex-atheist “flaunt[ing] his allegiance to deism” in May 2006 to a Christian audience at Biola University."

The New Zealand Association of Rationalists and Humanists has appointed Flew as an Honorary Associate.

Flew was awarded the Schlarbaum Prize by the Ludwig von Mises Institute for his "outstanding lifetime achievement in the cause of liberty." Upon acceptance of the award in Auburn, Alabama, in September 2001, Flew delivered an address entitled "Locke versus Rawls on Equality." Of his choice of topics, he stated "I am the first Englishman and the first professional philosopher to receive the Schlarbaum Prize. So it seems appropriate to begin by talking about the greatest English philosopher, John Locke."

On 11 May 2006, Antony Flew accepted the second "Phillip E. Johnson Award for Liberty and Truth" from evangelical Biola University. The award, named for its first recipient, was given to Flew "for his lifelong commitment to free and open inquiry and to standing fast against intolerant assaults on freedom of thought and expression". When informed of his award, Flew remarked, "In light of my work and publications in this area and the criticism I’ve received for changing my position, I appreciate receiving this award".