All we can do is search for the falsity content in our best theory.

True ignorance is not the absence of knowledge, but the refusal to acquire it.

The growth of knowledge depends entirely upon disagreement.

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.

The question is not how to get good people to rule; THE QUESTION IS: HOW TO STOP THE POWERFUL from doing as much damage as they can to us.

If you can't say it simply and clearly, keep quiet, and keep working on it till you can.

The best thing that can happen to a human being us to find a problem, to fall in love with that problem, and to live trying to solve that problem, unless another problem even more lovable appears.

Ignorance is not a simple lack of knowledge but an active aversion to knowledge, the refusal to know, issuing from cowardice, pride, or laziness of mind.

A theory which is not refutable by any conceivable event is non-scientific. Irrefutability is not a virtue of a theory (as people often think) but a vice.

I may be wrong and you may be right, and by an effort, we may get nearer to the truth

The attempt to make heaven on earth invariably produces hell.

Don’t allow the demands of work load

Ignorance is the parent of fear ...

A philosopher is a sort of intellectual yokel who gawks at things that sensible people take for granted.

My mum used to say to me, 'Spit on yer 'ands and take a fresh 'old.' Keep going even if you have setbacks.

If you worry, you die. If you don't worry, you also die. So why worry?

I don't know how you get dressed if you live in Wales, because it's pouring rain and then it's hot sunshine, and then it might hail. It's just so confusing.

Although it wasn't that easy to do, it was wonderful working with John Wayne.

Life is like the ocean, it goes up and down.

Are you afraid of the good you might do?