"No rational argument will have a rational effect on a man who does not want to adopt a rational atti..." — Karl Popper

Piecemeal social engineering resembles physical engineering in regarding the ends as beyond the province of technology.

We must plan for freedom, and not only for security, if for no other reason than that only freedom can make security secure.

Science must begin with myths, and with the criticism of myths.

We have become makers of our fate when we have ceased to pose as its prophets.