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.

I always wonder when it was that I was embraced.

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

We think that life develops spontaneously on Earth, so it must be possible for life to develop on suitable planets elsewhere in the universe. But we don’t know the probability that a planet develops life.

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

There is nothing more difficult to take in hand, more perilous to conduct, or more uncertain in its success, than to take the lead in the introduction of a new order of things.

Often one postulates that a priori, all states are equally probable. This is not true in the world as we see it. This world is not correctly described by the physics which assumes this postulate.

Life is anything but predictable.

I will carry on writing, to be sure. But I don’t know if I would want to publish again after Harry Potter.

I don’t like to commit myself about heaven and hell – you see, I have friends in both places.

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.

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.

We do not know what is really good or bad fortune.

The most distressing thing that can happen to a prophet is to be proved wrong. The next most distressing thing is to be proved right.

Waking up every day and loving someone who may or may not love us back, whose safety we can’t ensure, who may stay in our lives or may leave without a moment’s notice, who may be loyal to the day they die or betray us tomorrow – that’s vulnerability.

Risk comes from not knowing what you’re doing.

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

The truth is you don’t know what is going to happen tomorrow. Life is a crazy ride, and nothing is guaranteed.

You can’t learn in school what the world is going to do next year.

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

Fortune brings in some boats that are not steered.

I would never die for my beliefs because I might be wrong.

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.

Everything can change at any moment, suddenly and forever.

Talent without discipline is like an octopus on roller skates. There’s plenty of movement, but you never know if it’s going to be forward, backwards, or sideways.

A wet spot on the floor kind of put a scare in myself, so you never know inside those lines what might happen.

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

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

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

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

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

Change is always tough. Even for those who see themselves as agents of change, the process of starting a new thing can cause times of disorientation, uncertainty and insecurity.

You are 27 or 28 right? It is very tough to live at that age. When nothing is sure. I have sympathy with you.

It’s hard to speculate what tomorrow may bring.

I don’t have all the answers.

I’m a spokesman for myself. It just so happens that there’s a bunch of people that are concerned with what I have to say. I find that frightening at times because I’m just as confused as most people. I don’t have the answers for anything.

It is only by risking our persons from one hour to another that we live at all. And often enough our faith beforehand in an uncertified result is the only thing that makes the result come true.

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.

In this quest to seek and find God in all things, there is still an area of uncertainty. There must be. If a person says that he met God with total certainty and is not touched by a margin of uncertainty, then this is not good.

Prepare for the unknown by studying how others in the past have coped with the unforeseeable and the unpredictable.

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

The more I see the less I know for sure.

This suspense is terrible. I hope it will last.

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.

Vulnerability is basically uncertainty, risk, and emotional exposure.

As soon as questions of will or decision or reason or choice of action arise, human science is at a loss.

Our lifelong certainties about the world can be demolished in a single second.

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.

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

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!

You know, people talk about this being an uncertain time. You know, all time is uncertain. I mean, it was uncertain back in – in 2007, we just didn’t know it was uncertain. It was – uncertain on September 10th, 2001. It was uncertain on October 18th, 1987, you just didn’t know it.

He that waits upon fortune, is never sure of a dinner.

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.

Our need for certainty in an endeavor as uncertain as raising children makes explicit ‚how-to-parent‘ strategies both seductive and dangerous.

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

There are many things that I don’t understand.

For my part I know nothing with any certainty, but the sight of the stars makes me dream.

You never know with these things when you’re trying something new what can happen. This is all experimental.

We are like boxers, one never knows how much longer one has.

Not only do I not know what’s going on, I wouldn’t know what to do about it if I did.

It is a curious historical fact that modern quantum mechanics began with two quite different mathematical formulations: the differential equation of Schroedinger and the matrix algebra of Heisenberg. The two apparently dissimilar approaches were proved to be mathematically equivalent.