Argument is conclusive but it does not remove doubt so that the mind may rest in the sure knowledge of the truth unless it finds it by the method of experiment.

We know accurately only when we know little with knowledge doubt increases.

Doubt grows with knowledge.

Jealousy lives upon doubts. It becomes madness or ceases entirely as soon as we pass from doubt to certainty.

Artificial Intelligence leaves no doubt that it wants its audiences to enter a realm of pure fantasy when it identifies one of the last remaining islands of civilization as New Jersey.

My understanding is that what was provided was general order of battle information not operational intelligence. I certainly have no knowledge of US participation in preparing battle and strike packages and doubt strongly that that occurred.

Wonder rather than doubt is the root of all knowledge.

You will certainly not doubt the necessity of studying astronomy and physics if you are desirous of comprehending the relation between the world and Providence as it is in reality and not according to imagination.

And by the way everything in life is writable about if you have the outgoing guts to do it and the imagination to improvise. The worst enemy to creativity is self-doubt.

I doubt that the imagination can be suppressed. If you truly eradicated it in a child he would grow up to be an eggplant.

What I hope is in five years' time I can go to the British people in the election and say: Lots of you doubted that coalition politics worked but it has worked.

One must always hope when one is desperate and doubt when one hopes.

I doubt I'll be singing forever because at some point people aren't going to want to hear my music and I hope that I'll still get the opportunity to write songs.

Isn't it the moment of most profound doubt that gives birth to new certainties? Perhaps hopelessness is the very soil that nourishes human hope perhaps one could never find sense in life without first experiencing its absurdity.

I think people really marry far too much it is such a lottery after all and for a poor woman a very doubtful happiness.

I have my moments. Ever since I was a boy I never was someone who was at ease with happiness. Too often I embrace introspection and self-doubt. I wish I could embrace the good things.

Great leaders are almost always great simplifiers who can cut through argument debate and doubt to offer a solution everybody can understand.

The first test of a truly great man is his humility. By humility I don't mean doubt of his powers or hesitation in speaking his opinion but merely an understanding of the relationship of what he can say and what he can do.

There is a Western world. There is America. There is Great Britain and Germany and France and Russia and China and other nations. I doubt that there is one country amongst those I mentioned which has a desire to see Iran with its fundamentalist Islamic extremist government possessing nuclear weapons.

Look at our Lords disciples. One denied Him one doubted Him one betrayed Him. If our Lord couldn't have perfection how are you going to have it in city government?

Our laws governing lobbying and campaign contributions have struck the right balance between the wishes of the people and those of private industry so why are we so quick to doubt that the same great results can be achieved by putting the government's justice-dealing branch on the same market-based course?

I have no doubt that the government of this great nation will work with its people to lead New Orleans and the Gulf Coast back to an enlightened proud safe part of the world.

I have no doubt but that the misery of the lower classes will be found to abate whenever the Government assumes a freer aspect and the laws favor a subdivision of Property.

And I have no doubt that every new example will succeed as every past one has done in showing that religion and Government will both exist in greater purity the less they are mixed together.