Karl Popper

No rational argument will have a rational effect on a man who does not want to adopt a rational attitude.

Those who promise us paradise on earth never produced anything but a hell.

In so far as a scientific statement speaks about reality, it must be falsifiable; and in so far as it is not falsifiable, it does not speak about reality.

Be kind and considerate with your criticism... It's just as hard to write a bad book as it is to write a good book.

It is hardly surprising that women concentrate on the way they look instead of what is in their minds since not much has been put in their minds to begin with.

A myth is a lie that conceals or reveals a truth. But if it reveals even a strand of history or truth, that's what gets my adrenaline going.