When picking your way through the argument, it is as important to keep your eye on the critics of liberal orthodoxy as the orthodox themselves. Unlike many of his opponents, I do not believe that it is now fair to describe Ramadan as an Islamist. Whatever he believed in the past, no militant in the Muslim Brotherhood could have written a book like his latest, The Quest for Meaning (Allen Lane). It does not seek to cast a cloak of academic respectability over the justifications for wife-beating, female genital mutilation, the execution of homosexuals and the mass murder of the Jews that come from the Brotherhood's pre-eminent scholar, Yusuf al-Qaradawi. It does not appear to be the work of any kind of sectarian, but rather of a turgid ecumenicist. Platitudes stumble through its pages like weary travellers looking for rest. "We have to become adults whether we like it or not," he says of growing old. "The first steps are indeed the hardest," he says of the spiritual journey he wishes us to follow. After reading the first chapters, I had to concede he was right. He examines competing religions and finds in true Thought for the Day fashion that what unites them is more important than what divides them. If only everyone recognised the common ground, we would understand "the other as he is, his way of thinking, his emotional and affective reactions from where he stands without prejudging anything". Like Dr Casaubon, Ramadan has produced a Key to All Mythologies, which is as dry and pedantic in life as it was in George Eliot's fiction.

Only if you read him closely do you grasp why so many French thinkers regarded him with suspicion before he moved to Britain. For what does he mean when he says we should not prejudge "the other"? Ramadan studied at Geneva University and the continental school of philosophy rarely teaches its students the virtues of clarity. On one question, however, Ramadan speaks plainly. The religious tolerance of the Enlightenment is not good enough for him. Tolerance means suffering the presence of "the other", he says. Only when we move from tolerance to respect will we "recognise that the other is as complex as we are; he is our equal, our mirror, our question". 

Forget the sanctimonious sentiments for a moment. Forget, too, that Ramadan refuses to condemn or even mention the religious oppression and violence in much of the Muslim world, and consider what he is asking us to throw away. Religious tolerance received its classic Enlightenment definition in Thomas Jefferson's Virginia Statute for Religious Freedom of 1777: "No man shall be compelled to frequent or support any religious worship, place, or ministry whatsoever...All men shall be free to profess, and by argument to maintain their opinions in matters of religion." 

Jefferson's key phrase was "by argument". Toleration did not limit debate but removed the barriers of state and church that had stood in debate's way. Argument is not in its nature always respectful of "the other's" point of view. At its best, it is robust and demanding. Ramadan's insistence on "respect" is a way of erecting new barriers in place of old, of ruling debates off limits. 

He has been saying throughout his career that we must bite our tongues. He left France after Nicolas Sarkozy challenged him on TV to condemn outright the stoning to death of adulterous women. Ramadan could not do it. The best he could manage was to mutter that he wished to see a "moratorium" on religious murder. The French journalist Caroline Fourest described his tendency to look liberal while refusing come out against anti-liberal causes as "Ramadan's double-speak". He appears not to condone Qaradawi's cruelty, then appears to ally with Qaradawi. He appears to condemn Islamist violence to one audience, but not to another.