I HAVE NOTHING OF MY own to add to the essays on the history of ideas contained in this book, but I should be exceedingly remiss if I did not take this opportunity of offering my thanks to Mr Roger Hausheer for providing so sympathetic and luminous an account of my views on the topics discussed in these essays. No author could wish for a more understanding, scrupulous or civilised critic. I should like to express my sincere thanks to this most promising young scholar.
Isaiah Berlin
September 1978