John Maynard Keynes Quotes

Reasoning draws a conclusion, but does not make the conclusion certain, unless the mind discovers it by the path of experience.

From principles is derived probability, but truth or certainty is obtained only from facts.

Guessing isn't knowing.

Even though there are no ways of knowing for sure, there are ways of knowing for pretty sure.

All knowledge degenerates into probability.

No human being will ever know the Truth, for even if they happen to say it by chance, they would not even known they had done so.

When you have eliminated the impossible, whatever remains, however improbable, must be the truth.

A thousand probabilities don't make one fact.

There is only one thing about which I am certain, and that is that there is very little about which one can be certain.

In practical life we are compelled to follow what is most probable ; in speculative thought we are compelled to follow truth. A man would perish of hunger and thirst, if he refused to eat or drink, till he had obtained positive proof that food and drink would be good for him. But in philosophic reflection this is not so. On the contrary, we must take care not to admit as true anything, which is only probable. For when one falsity has been let in, infinite others follow.

Except in pure mathematics, nothing is known for certain (although much is certainly false).

Suspecting and knowing are not the same.

Certainty is no guarantor of correctness.

A great deal more is known than has been proved.

I have throughout been curious about how much we can be said to know and with what degree of certainty or doubtfulness.

All knowledge resolves itself into probability. ... In every judgment, which we can form concerning probability, as well as concerning knowledge, we ought always to correct the first judgment deriv'd from the nature of the object, by another judgment, deriv'd from the nature of the understanding.

God forbid that Truth should be confined to Mathematical Demonstration!

Even if all parts of a problem seem to fit together like the pieces of a jigsaw puzzle, one has to remember that the probable need not necessarily be the truth and the truth not always probable.

For me the problem of induction is a problem about the world: a problem of how we, as we are now (by our present scientific lights), in a world we never made, should stand better than random, or coin-tossing chances changes of coming out right when we predict by inductions. . . .

Guessing a thing ain't knowing a thing.

Even the stoics agree that certainty is very hard to come at; that our assent is worth little, for where is infallibility to be found?

...skepticism can never provide firm ground under a man's feet. And perhaps, after all, we need firm ground.

How wrong people always were when they said: 'It's better to know the worst than go on not knowing either way.' No; they had it exactly the wrong way round. Tell me the truth, doctor, I'd sooner know. But only if the truth is what I want to hear.

Seeing is believing and believing is knowing and knowing beats unknowing and the unknown.

If WE claim only reasonable probability, it will be as much as men who love the truth can ever at any given moment hope to have within their grasp.