It is only fitting that this book should begin with an expression of the author's gratitude to the founder of the Wiles Lectures, to the Vice-Chancellor of The Queen's University, Belfast, and to Professor Michael Roberts and his colleagues, both for the invitation to deliver the lectures and for everything that makes them such an enjoyable occasion for the lecturer. I must also thank my friends and fellow-students of the history of the French Revolution, who honoured me by attending the lectures and discussing them with me afterwards.

The intention of the founder of the Wiles Lectures, as I understand it, was not to endow detailed research, but to promote reflection about historical problems. In my lectures, and in the book which is based on them, I have tried to meet this requirement while recognising the risks it brings with it. In the first place, this is bound to be in some respects a critical activity. Historical research can be, and perhaps usually is, done within the limits of an accepted pattern. Reflection about history brings with it the possibility of wanting to change the pattern. When, as in the case of the French Revolution, it is a well-established pattern, consolidated by a series of great historians, with long accepted theoretical implications, any attempt to question it is likely to meet with automatic and authoritative resistance. The resistance will be all the stronger if it seems that a formula which appeared to explain the revolution satisfactorily is being discarded, without another being provided to take its place. This, I fear, is what I am doing.