At puberty, the elements of an unsuperstitious sexual morality ought to be taught. Boys and girls should be taught that nothing can justify sexual intercourse unless there is mutual inclination... Boys and girls should be taught respect for each other's liberty; they should be made to feel that nothing gives one human being rights over another, and that jealousy and possessiveness kill love. They should be taught that to bring another human being into the world is a very serious matter, only to be undertaken when the child will have a reasonable prospect of health, good surroundings, and parental care. But they should also be taught methods of birth control, so as to insure that children shall only come when they are wanted. Finally, they should be taught the dangers of venereal disease, and the methods of prevention and cure. The increase of human happiness to be expected from sex education on these lines is immeasurable.

Knowledge is not so precise a concept as is commonly thought. Instead of saying "I know this," we ought to say "I more or less know something more or less like this." It is true that this proviso is hardly necessary as regards the multiplication table, but knowledge in practical affairs has not the certainty or the precision of arithmetic. Suppose I say "democracy is a good thing": I must admit, first, that I am less sure of this than I am that two and two are four, and secondly, that "democracy" is a somewhat vague term which I cannot define precisely. We ought to say, therefore: "I am fairly certain that it is a good thing if a government has something of the characteristics that are common to the British and American Constitutions," or something of this sort. And one of the aims of education ought to be to make such a statement more effective from a platform than the usual type of political slogan.

Man is a credulous animal, and must believe something; in the absence of good grounds for belief, he will be satisfied with bad ones.

Love is wise; hatred is foolish. In this world, which is getting more and more closely interconnected, we have to learn to tolerate each other, we have to learn to put up with the fact that some people say things that we don't like. We can only live together in that way. But if we are to live together, and not die together, we must learn a kind of charity and a kind of tolerance, which is absolutely vital to the continuation of human life on this planet.

We thus have a kind of see-saw: first, pure persuasion leading to the conversion of a minority; then force exerted to secure that the rest of the community shall be exposed to the right propaganda; and finally a genuine belief on the part of the great majority, which makes the use of force again unnecessary.