The first edition of this book was written a little over forty years ago, the second about twenty years later. In this third edition, as in the second, I have chosen to leave the original material for the most part unchanged; references in parts I-III are to the world c. 1970, in part IV to the world c. 1988. I have added a few footnotes and notes at the ends of some chapters, in square brackets and a different font, commenting on events that occurred after the chapter was written or pointing at relevant new material later in the book. Since my subject is ideas, not history, I see little point in trying to keep the old chapters current; with luck, this edition will still be being read at a point when the details of 2014 are almost as out of date as the details of 1970. I have also converted all references to “private protection agencies” into “rights enforcement agencies”, because too many people associated the former term with the protection racket, extortion disguised as protection.

What I have added in this edition, aside from minor stylistic changes—forty years ago I was much too fond of commas, scare quotes, and long dashes—is in parts V and VI. Part V contains later, I hope deeper, thoughts on my earlier ideas, part VI new material. The hardcopy version you are reading contains a few minor changes from the Kindle version.

What have I learned in forty year?
The answer is not clear, I fear,
But some of it, at least, is here.