Karl R. Popper said this quote

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

~ Karl R. Popper

Aestheticism and radicalism must lead us to jettison reason, and to replace it by a desperate hope for political miracles. This irrational attitude which springs from intoxication with dreams of a beautiful world is what I call Romanticism. It may seek its heavenly city in the past or in the future; it may preach ‘back to nature’ or ‘forward to a world of love and beauty’; but its appeal is always to our emotions rather than to reason. Even with the best intentions of making heaven on earth it only succeeds in making it a hell – that hell which man alone prepares for his fellow-men.

~ Karl R. Popper

Whenever a theory appears to you as the only possible one, take this as a sign that you have neither understood the theory nor the problem which it was intended to solve.

~ Karl R. Popper

While differing widely in the various little bits we know, in our infinite ignorance we are all equal.

~ Karl R. Popper