“The wise man belongs to all countries, for the home of a great soul is the whole world.”

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

Science is most significant as one of the greatest spiritual adventures that man has yet known.

And it implies that if we respect truth, we must search for it by persistently searching for our errors: by indefatigable rational criticism, and self-criticism.

Instead of the greatest happiness for the greatest number, one should demand, more modestly, the least amount of avoidable suffering for all.

I would rather find a single causal law than be the king of Persia!

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

All life is problem-solving.

In my view, aiming at simplicity and lucidity is a moral duty of all intellectuals: lack of clarity is a sin, and pretentiousness is a crime.

He who decides one day that scientific statements do not call for any further test and that they can be regarded as finally verified retires from the game.

The way of science is paved with discarded theories that were once declared self-evident.

The method of learning by trial and error – of learning from our mistakes – seems to be fundamentally the same whether it is practiced by lower or by higher animals, by chimpanzees, or by men of science.

In philosophy methods are unimportant; any method is legitimate if it leads to results capable of being rationally discussed.

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.

Theology, I still think, is due to a lack of faith.

Science may be described as the art of systematic oversimplification.

The game of science is, in principle, without end.

A great country worthy of the name does not have any friends.

I often speak publicly, and when I do, I also get to listen to other presenters. The most memorable are the ones that hit an emotional chord with a tight story and a punch line. No fluff. Keep it creative and concise. Greatness exists in quality, not quantity.

But what is liberty without wisdom, and without virtue? It is the greatest of all possible evils; for it is folly, vice, and madness, without tuition or restraint.

Greatness is a road leading towards the unknown.

Thanks to my work everything’s going well; it’s a great consolation.

The greatest test of a man’s character is his tongue.

In other words, don’t expect to always be great. Disappointments, failures and setbacks are a normal part of the lifecycle of a unit or a company and what the leader has to do is constantly be up and say ‘we have a problem, let’s go and get it’.

Have a sense of humor to break the tension in times of great toil.