Science and engineering have given us physical powers that were historically thought of as belonging only to the gods. In the Judeo-Christian tradition, only God could destroy cities with thunderbolts. Today we can do the same with nuclear weapons. Only God could cause a flood that would necessitate Noah building an ark, whereas human-induced global warming threatens similar devastation. Only God could create new life-forms. Today we do that with genetic engineering.

In contrast to the godlike physical power that technology has given us, humanity’s ethical progress is, at best, at the irresponsible adolescent phase, creating a technological imperative—a requirement—for accelerating our ethical evolution. Humanity is like a 16-year-old with a new driver’s license who somehow got his hands on a 500-horsepower Ferrari. We will either grow up really fast or we will kill ourselves.

Society behaves as if the various threats we face are tolerable, so let us look at the greatest immediate risk—the only man-made threat that could destroy civilization as you read this: nuclear war. I have asked hundreds of people how many years they think nuclear deterrence can be expected to work before it fails and destroys civilization as we know it. Because that is a hard number to quantify, I ask them to do this only to an order of magnitude—the nearest power of 10.

While there are exceptions, almost everyone sees 10 years as too short for this “nuclear time horizon” and 1,000 years as too long. That leaves 100 years as their order–of-magnitude estimate, which corresponds to a risk of roughly 1 percent per year. Over the next decade, that corresponds to almost 10 percent, and it results in less than even odds over the life expectancy of a child born today in the U.S.

The risk can be seen more vividly by imagining a man wearing a TNT vest sat down next to you and, before you could escape, told you he wasn’t a suicide bomber. He didn’t have the button for setting off the explosives. Rather, there were two buttons in very safe hands. One was in Washington, D.C., with President Donald Trump, so just sit back and relax. The other was in Moscow, with President Vladimir Putin, so again, there was nothing to worry about. You’d still get away as fast as you could.

Just because we can’t see the nuclear weapons controlled by those two buttons, why would we stay in this situation? As if confronted by that man in the TNT vest, we need to be plotting a rapid escape. Instead we have sat here, complacently, for more than 50 years, trusting that because the earth’s explosive vest hasn’t yet gone off, it never will.

Given that accelerating our ethical evolution is essential for humanity’s progress to continue, the next question becomes: “Is there any hope of doing that?” I know there is hope of success because I have experienced it personally, transforming a marriage that was on the brink of divorce to one where my wife and I thank each other daily for the little bit of heaven we have brought down to earth. (For details, go to

A second reason for hope may seem paradoxical: many people tell me I am on a fool’s errand. That is hopeful because most of the best ideas appear foolish before they pay off. All of my colleagues initially discouraged me from working in cryptography, yet that eventually led to my winning the Association for Computing Machinery’s A. M. Turing Award, the top prize in computer science and the reason I was invited to deliver a talk at this year’s Lindau Nobel Laureate Meeting.

While there, I asked five of the Nobel laureates about their prizewinning work, and all but one had been discouraged from undertaking it. Dan Shechtman, who won the 2011 Nobel Prize in Chemistry for his work on quasicrystals, told me that two-time Nobel laureate Linus Pauling had even derided him as a “quasi scientist.” Most great achievements appear foolish a priori, including saving humanity from itself.

A third element of hope is that we need to accelerate humanity’s ethical evolution, not start the process from scratch. Over the past two centuries, many parts of the world have done what earlier seemed impossible. They abolished slavery, established universal suffrage, improved human rights and started to tackle environmental degradation, including climate change.

We have even made significant progress on the nuclear threat. The world’s arsenal has fallen from a peak of approximately 70,000 warheads in 1986 to 14,000 today, an 80 percent reduction. Such a reduction was unimaginable just a few decades ago. If enough of us work at accelerating humanity’s ethical evolution, together we will not only triumph over the threats we face; we will also build a more peaceful, sustainable world we can be proud to pass on to future generations.

I will close with a lesson that I learned from one of my primary mentors. There are two hypotheses: either we are capable of the great changes needed to ensure humanity’s survival—that’s the nobler hypothesis—or we are not. If we assume the less noble hypothesis, we will be doomed even if we have the capacity to change. But if we assume the nobler hypothesis, the worst that happens is we go down fighting. And the best that happens is humanity continues its awesome evolutionary arc. “Why not assume the nobler hypothesis?” my mentor concluded. It made sense to me then, and it still does today.

This editorial is excerpted from a talk I presented at this year’s Lindau Nobel Laureate Meeting. A recording of the talk and a more complete written version are available at