'In the forty years it took me to write this book, I only gradually realized that the finished work, if it were going to be true to the pattern of my experience, would have no pattern . . . The book I wanted to write had its origins in the books I was reading. Several times, in my early days, I had to sell my best books to buy food, so I never underlined anything. When conditions improved I became less fastidious. Not long after I began marking passages for future consideration, I also began keeping notes in the margin beside the markings, and then longer notes on the endpapers . . . As the time for assembling my reflections approached, I resolved that a premature synthesis was the thing to be avoided. So this is a book about how not to reach one. If I have done my job properly, themes will emerge from the apparent randomness and make this work intelligible. But it will undoubtedly be a turbulent read, and if this book were not difficult, it would not be true.' A lifetime in the making