Whenever one writes a book one should have a notional reader in mind.

I think there's a real danger that Islamophobia can actually be a cover for something far more malign. I don't want to sound like a spokesman for the Muslim Arbitration Tribunal but I am a supporter of autonomy for religious communities and for non-discrimination.

If Muslims want to take their disputes to religious arbitrators because they genuinely believe that it's a matter of great spiritual importance that they do that, they shouldn't be the only community in this country that's denied the opportunity to do that. Because the Jewish population has been entitled to take their disputes to tribunals known as the Beth Din for over one hundred years, and the Church of England is integrated into the fabric of this country, and there are ecclesiastical tribunals where religious disputes can be dealt with.

There have been lots and lots of fatwas against violence. But it is an interesting question. A Mufti is the person that issues the fatwa and you'll find Muftis at all the Madrasas. Basically once you've studied for long enough you have the authority to issue a fatwa. But there are limits. I can bang on and on on the point but all I'm really saying is that there isn't a simple answer.

Ayatollah Khomeini issued a fatwa to that effect, which was then given effect in the Islamic Republic of Iran, so in the Islamic Republic of Iran, it's flexible enough to allow for sex changes, and it encourages sex changes. But if you want to change your religion in Iran, you've got some serious problems. There are other problems. You're allowed to change sex, but if you want to be a homosexual, theoretically at least, you face the death penalty. Quite how often these penalties are carried out is a moot point, but it's there on the statute books.

There's crucial distinction that has to be drawn between the Shari'a, which is this hugely expansive vision of cosmic order that I've been describing, and principles of Islamic law, known in Arabic as "Fiqh" - a word that means understanding. If you're a devout Muslim, you don't argue against the Shari'a; the Shari'a is the path that God has laid down. But what you can do, and what people are doing all the time, is arguing over the correct interpretation of the Shari'a, arguing over the Fiqh. That's something that has been going on throughout Islamic history.

I was a teenager when General Zia took power in the Pakistan; I was in my twenties when I went there during the late 1980s and I saw then not only the novel punishments that he was introducing - because they were novel, and this is again something that's very important to understand, it's only in the last thirty, forty years, since 1979 in fact, that these penalties have been revived anywhere in the world apart from Saudi Arabia.