Stanley Benn completed A Theory of Freedom shortly before his death in July 1986. Each chapter had been rewritten several times, and he considered the arguments as sound as he could make them. He was, however, unable to make the final stylistic revisions he had intended, and in preparing his text for publication we have generally refrained from doing this for him. For the sake of clarity some punctuation has been adjusted and the occasional sentence reshaped, but we have altered his words as little as possible. Consequently his use of man and of masculine pronouns to refer to humans in general remains; he was never happy with this feature of English but rebelled when asked to use substitute expressions he considered clumsy. We had no wish to alter his prose in a way he would have resisted. A Theory of Freedom is not merely Stanley Benn's last philosophic work, it is the summation of those beliefs by which he lived. The book speaks with the author's voice, not ours; those who knew him will recognize it.