The study of history is a powerful antidote to contemporary arrogance. It is humbling to discover how many of our glib assumptions, which seem to us novel and plausible, have been tested before, not once but many times and in innumerable guises; and discovered to be, at great human cost, wholly false.

A Stalin functionary admitted, Innocent people were arrested: naturally - otherwise no one would be frightened. If people were arrested only for specific misdemeanours, all the others would feel safe and so become ripe for treason.

If we want foxes, to observe and delight in, we must have hunting.

The writer learns to write, in the last resort, only by writing. He must get words onto paper even if he is dissatisfied with them.

In the long term, it is desirable that the human race, faced with the prospect of extinction on Earth, should prepare an escape route for itself to another inhabitable planet.

If the decline of Christianity created the modern political zealot - and his crimes - so the evaporation of religious faith among the educated left a vacuum in the minds of Western intellectuals easily filled by secular superstition. There is no other explanation for the credulity with which scientists, accustomed to evaluating evidence, and writers, whose whole function was to study and criticize society, accepted the crudest Stalinist propaganda at its face value. They needed to believe; they wanted to be duped.

In 1924 Mao took a Chinese friend, newly arrived from Europe, to see the notorious sign in the Shanghai park, 'Chinese and Dogs Not Allowed'.