Why should we, however, in economics, have to plead ignorance of the sort of facts on which, in the case of a physical theory, a scientist would certainly be expected to give precise information?

To undertake the direction of the economic life of people with widely divergent ideals and values is to assume responsibilities which commit one to the use of force; it is to assume a position where the best intentions cannot prevent one from being forced to act in a way which to some of those affected must appear highly immoral. This is true even if we assume the dominant power to be as idealistic and unselfish as we can possibly conceive. But how small is the likelihood that it will be unselfish, and how great are the temptations!

Freedom can be preserved only if it is treated as a supreme principle which must not be sacrificed for particular advantages.

It may be that a free society... carries in itself the forces of its own destruction, that once freedom has been achieved it is taken for granted and ceases to be valued, and that the free growth of ideas which is the essence of a free society will bring about the destruction of the foundations on which it depends.

Socialist thought owes its appeal to the young largely to its visionary character; the very courage to indulge in Utopian thought is in this respect a source of strength for socialism which traditional liberalism sadly lacks. Speculation about general principles provides an opportunity for the play of the imagination of those who are unencumbered by much knowledge of the facts of present-day life. Their ideas suffer from inherent contradictions, and any attempt to put them into practice must produce something utterly different from what they expect.

To act on the belief that we possess the knowledge and the power which enable us to shape the processes of society entirely to our liking, knowledge which in fact we do not possess, is likely to make us do much harm.

It is rather a problem of how to secure the best use of resources known to any of the members of society, for ends whose relative importance only those individuals know.