If we have an atom that is in an excited state and so is going to emit a photon, we cannot say when it will emit the photon. It has a certain amplitude to emit the photon at any time, and we can predict only a probability for emission; we cannot predict the future exactly.

America is not nearly done. We’re only in the beginning. Who knows who we will be? Who knows… what color we will be? It is all something that, maybe, our descendants – if they survive that long – will see.

There’s no point in making predictions. It’s not worth speculating because nothing is set in stone and things change all the time in football. Today there are opportunities that no one knows if they will come round again in the future.

To some extent I happily don’t know what I’m doing. I feel that it’s an artist’s responsibility to trust that.

It’s hard to speculate what tomorrow may bring.

If a man will begin with certainties, he shall end in doubts, but if he will content to begin with doubts, he shall end in certainties.

When God sneezed, I didn’t know what to say.

God not only plays dice, but also sometimes throws them where they cannot be seen.

I’m not a fortune-teller.

And no, we don’t know where it will lead. We just know there’s something much bigger than any of us here.

Things on a very small scale behave like nothing that you have any direct experience about. They do not behave like waves, they do not behave like particles, they do not behave like clouds, or billiard balls, or weights on springs, or like anything that you have ever seen.

Life is a constant oscillation between the sharp horns of dilemmas.

Either he’s dead or my watch has stopped.

If you only do things where you know the answer in advance, your company goes away.

This is the first age that’s ever paid much attention to the future, which is a little ironic since we may not have one.

The uncertainty of parenting can bring up feelings in us that range from frustration to terror.

‚Tis better to bear the ills we have than fly to others that we know not of.

From the time I was a kid, I always knew something was going to happen to me. Didn’t know exactly what.

‚In Utero‘ was the first time I’d made an album that reached into the dark side. I remember the conflict and the uncertainty. I remember all those things when I hear ‚Pennyroyal Tea.‘

Fortune brings in some boats that are not steered.

What prudent merchant will hazard his fortunes in any new branch of commerce when he knows not that his plans may be rendered unlawful before they can be executed?

If there’s one thing that’s certain in business, it’s uncertainty.

U2’s best work has always been when we didn’t know what we’re doing.

We sail within a vast sphere, ever drifting in uncertainty, driven from end to end.

I’m very careful about saying who would and wouldn’t go to heaven. I don’t know.

I believe the most solemn duty of the American president is to protect the American people. If America shows uncertainty and weakness in this decade, the world will drift toward tragedy. This will not happen on my watch.

The true and the approximately true are apprehended by the same faculty; it may also be noted that men have a sufficient natural instinct for what is true, and usually do arrive at the truth. Hence the man who makes a good guess at truth is likely to make a good guess at probabilities.

Scientific views end in awe and mystery, lost at the edge in uncertainty, but they appear to be so deep and so impressive that the theory that it is all arranged as a stage for God to watch man’s struggle for good and evil seems inadequate.

Would you bet your paycheck on a weather forecast for tomorrow? If not, then why should this country bet billions on global warming predictions that have even less foundation?

I cannot discover that anyone knows enough to say definitely what is and what is not possible.

Truth is so obscure in these times, and falsehood so established, that, unless we love the truth, we cannot know it.

Often, I can scarcely hear any one speaking to me; the tones yes, but not the actual words; yet as soon as any one shouts, it is unbearable. What will come of all this, heaven only knows!

It is not scientifically possible to accurately predict the outcome of an action. To suggest otherwise runs contrary to historical experience and the nature of war.

I don’t know what ‚normal‘ means, anyway.

In such a porcelain life, one likes to be sure that all is well lest one stumble upon one’s hopes in a pile of broken crockery.

The Lord can give, and the Lord can take away. I might be herding sheep next year.

The more I see the less I know for sure.

Doing what’s right isn’t the problem. It is knowing what’s right.

We know what we are, but know not what we may be.

A hustler has to deal with danger and risk. It’s part of the game. You cannot control it all, nor would you want to. Chaos, unknown factors are not something to be anxious about.

The probability of apocalypse soon cannot be realistically estimated, but it is surely too high for any sane person to contemplate with equanimity.

Do not keep saying to yourself, if you can possibly avoid it, ‚But how can it be like that?‘ because you will get ‚down the drain,‘ into a blind alley from which nobody has yet escaped. Nobody knows how it can be like that.

I don’t know what can be so dangerous about giving people hope.

It has not yet become obvious to me that there’s no real problem. I cannot define the real problem; therefore, I suspect there’s no real problem, but I’m not sure there’s no real problem.

Faith keeps many doubts in her pay. If I could not doubt, I should not believe.

I really want to love somebody. I do. I just don’t know if it’s possible forever and ever.

I want to marry Arline because I love her – which means I want to take care of her. That is all there is to it. I want to take care of her. I am anxious for the responsibilities and uncertainties of taking care of the girl I love.

Younger people have greatest fears. Why is that? Because they don’t know the plot. They don’t know their own individual plot… they don’t know what’s going to happen to them.

God not only plays dice, He also sometimes throws the dice where they cannot be seen.

The action we take and the decisions we make in this decade will have consequences far into this century. If America shows weakness and uncertainty, the world will drift toward tragedy. That will not happen on my watch.

Success isn’t supposed to happen, no matter how hard you work. There’s no guarantee you’re going to succeed. There’s nothing set in stone.

Being at ease with not knowing is crucial for answers to come to you.

As far as the laws of mathematics refer to reality, they are not certain, and as far as they are certain, they do not refer to reality.

There are too many accidents that can befall life on a single planet.

I accept chaos, I’m not sure whether it accepts me.

We are afraid to care too much, for fear that the other person does not care at all.

The probability that we may fail in the struggle ought not to deter us from the support of a cause we believe to be just.

We fear that this moment will end, that we won’t get what we need, that we will lose what we love, or that we will not be safe. Often, our biggest fear is the knowledge that one day our bodies will cease functioning. So even when we are surrounded by all the conditions for happiness, our joy is not complete.

I might just write a novel next. I don’t know!

The first two games for Churchill, I was so jittery that I didn’t know what to do. I was running more but didn’t know what to do. I’ve no bones accepting the fact that I didn’t know what was happening in the game.

Because the theory of quantum mechanics could explain all of chemistry and the various properties of substances, it was a tremendous success. But still there was the problem of the interaction of light and matter.