Life 3.0: Being Human in the Age of Artificial Intelligence

by Max Tegmark

life may independently originate in multiple places in our cosmos. In that case, unambitious civilizations simply become cosmically irrelevant, with ever-larger parts of the cosmic endowment ultimately being taken over by the most ambitious life forms. Natural selection therefore plays out on a cosmic scale and, after a while, almost all life that exists will be ambitious life. In summary, if we’re interested in the extent to which our cosmos can ultimately come alive, we should study the limits of ambition that are imposed by the laws of physics. Let’s do this! Let’s first explore the limits of what can be done with the resources (matter, energy, etc.) that we have in our Solar System, then turn to how to get more resources through cosmic exploration and settlement.

Whereas today’s supermarkets and commodity exchanges sell tens of thousands of items we might call “resources,” future life that’s reached the technological limit needs mainly one fundamental resource: so-called baryonic matter, meaning anything made up of atoms or their constituents (quarks and electrons). Whatever form this matter is in, advanced technology can rearrange it into any desired substances or objects, including power plants, computers and advanced life forms. Let’s therefore begin by examining the limits on the energy that powers advanced life and the information processing that enables it to think.

When we talked about energy use, he scoffed at how unambitious we humans were, pointing out that we could meet all our current global energy needs by harvesting the sunlight striking an area smaller than 0.5% of the Sahara desert. But why stop there? Why even stop at capturing all the sunlight striking Earth, letting most of it get wastefully beamed into empty space? Why not simply put all the Sun’s energy output to use for life?

The first challenge is that our Universe is expanding, which means that almost all galaxies are flying away from us, so settling distant galaxies amounts to a game of catch-up. The second challenge is that this cosmic expansion is accelerating, due to the mysterious dark energy that makes up about 70% of our Universe. To understand how this causes trouble, imagine that you enter a train platform and see your train slowly accelerating away from you, but with a door left invitingly open. If you’re fast and foolhardy, can you catch the train? Since it will eventually go faster than you can run, the answer clearly depends on how far away from you the train is initially: if it’s beyond a certain critical distance, you’ll never catch up with it. We face the same situation trying to catch those distant galaxies that are accelerating away from us: even if we could travel at the speed of light, all galaxies beyond about 17 billion light-years remain forever out of reach—and that’s over 98% of the galaxies in our Universe.

The two key problems are that conventional rockets spend most of their fuel simply to accelerate the fuel they carry with them, and that today’s rocket fuel is hopelessly inefficient—the fraction of its mass turned into energy isn’t much better than the 0.00000005% for gasoline that we saw in table 6.1. One obvious improvement is to switch to more efficient fuel. For example, Freeman Dyson and others worked on NASA’s Project Orion, which aimed to explode about 300,000 nuclear bombs during 10 days to reach about 3% of the speed of light with a spaceship large enough to carry humans to another solar system during a century-long journey.5 Others have explored using antimatter as fuel, since combining it with ordinary matter releases energy with nearly 100% efficiency.

Figure 6.8 illustrates a clever laser-sail rocket design pioneered in 1984 by Robert Forward, the same physicist who invented the statites we explored for Dyson sphere construction. Just as air molecules bouncing off a sailboat sail will push it forward, light particles (photons) bouncing off a mirror will push it forward. By beaming a huge solar-powered laser at a vast ultralight sail attached to a spacecraft, we can use the energy of our own Sun to accelerate the rocket to great speeds. But how do you stop? This is the question that eluded me until I read Forward’s brilliant paper: as figure 6.8 shows, the outer ring of the laser sail detaches and moves in front of the spacecraft, reflecting our laser beam back to decelerate the craft and its smaller sail.

Putting together everything we’ve explored in this chapter tells us that maximally efficient power plants and computers would enable superintelligent life to perform a mind-boggling amount of computation. Powering your thirteen-watt brain for a hundred years requires the energy in about half a milligram of matter—less than in a typical grain of sugar.

If we don’t improve our technology, the question isn’t whether humanity will go extinct, but merely how: will an asteroid, a supervolcano, the burning heat of the aging Sun or some other calamity get us first?

If we do keep improving our technology with enough care, foresight and planning to avoid pitfalls, life has the potential to flourish on Earth and far beyond for many billions of years, beyond the wildest dreams of our ancestors.

Table 7.1 shows how dominant humanity has become from the physics perspective: not only do we now contain more matter than all other mammals except cows (which are so numerous because they serve our goals of consuming beef and dairy products), but the matter in our machines, roads, buildings and other engineering projects

In my opinion, both this ethical problem and the goal-alignment problem are crucial ones that need to be solved before any superintelligence is developed. On one hand, postponing work on ethical issues until after goal-aligned superintelligence is built would be irresponsible and potentially disastrous. A perfectly obedient superintelligence whose goals automatically align with those of its human owner would be like Nazi SS-Obersturmbannführer Adolf Eichmann on steroids:

Since ancient times, philosophers have dreamt of deriving ethics (principles that govern how we should behave) from scratch, using only incontrovertible principles and logic. Alas, thousands of years later, the only consensus that has been reached is that there’s no consensus. For example, while Aristotle emphasized virtues, Immanuel Kant emphasized duties and utilitarians emphasized the greatest happiness for the greatest number. Kant argued that he could derive from first principles (which he called “categorical imperatives”) conclusions that many contemporary philosophers disagree with: that masturbation is worse than suicide, that homosexuality is abhorrent, that it’s OK to kill bastards, and that wives, servants and children are owned in a way similar to objects.

As regards goodness, the so-called Golden Rule (that one should treat others as one would like others to treat oneself) appears in most cultures and religions, and is clearly intended to promote the harmonious continuation of human society (and hence our genes) by fostering collaboration and discouraging unproductive strife.

A cursory reading of human history might suggest hints of such a convergence: in his book The Better Angels of Our Nature, Steven Pinker argues that humanity has been getting less violent and more cooperative for thousands of years, and that many parts of the world have seen increasing acceptance of diversity, autonomy and democracy. Another hint of convergence is that the pursuit of truth through the scientific method has gained in popularity over past millennia. However, it may be that these trends show convergence not of ultimate goals but merely of subgoals. For example, figure 7.2 shows that the pursuit of truth (a more accurate world model) is simply a subgoal of almost any ultimate goal.

Although Francis Crick warned Christof Koch about studying consciousness, Christof refused to give up and and eventually won Francis over. In 1990, they wrote a seminal paper about what they called “neural correlates of consciousness” (NCCs), asking which specific brain processes corresponded to conscious experiences. For thousands of years, thinkers had had access to the information processing in their brains only via their subjective experience and behavior. Crick and Koch pointed out that brain-reading technology was suddenly providing independent access to this information, allowing scientific study of which information processing corresponded to what conscious experience. Sure enough, technology-driven measurements have by now turned the quest for NCCs into quite a mainstream part of neuroscience, one whose thousands of publications extend into even the most prestigious journals.

Such NCC research has proven that none of your consciousness resides in your gut, even though that’s the location of your enteric nervous system with its whopping half-billion neurons that compute how to optimally digest your food; feelings such as hunger and nausea are instead produced in your brain. Similarly, none of your consciousness appears to reside in the brainstem, the bottom part of the brain that connects to the spinal cord and controls breathing, heart rate and blood pressure. More shockingly, your consciousness doesn’t appear to extend to your cerebellum (figure 8.3), which contains about two-thirds of all your neurons: patients whose cerebellum is destroyed experience slurred speech and clumsy motion reminiscent of a drunkard, but remain fully conscious.

In summary, your consiousness lives in the past, with Christof Koch estimating that it lags behind the outside world by about a quarter second. Intriguingly, you can often react to things faster than you can become conscious of them, which proves that the information processing in charge of your most rapid reactions must be unconscious.

Yet if you touch your nose, you consciously experience the sensation on your nose and fingertip as simultaneous, and if you clap your hands, you see, hear and feel the clap at exactly the same time.14 This means that your full conscious experience of an event isn’t created until the last slowpoke email reports have trickled in and been analyzed.

We can do this by building on what we learned in chapter 2 about how clumps of matter can have emergent properties that are related to information. We saw that for something to be usable as a memory device that can store information, it needs to have many long-lived states. We also saw that being computronium, a substance that can do computations, in addition requires complex dynamics: the laws of physics need to make it change in ways that are complicated enough to be able to implement arbitrary information processing. Finally, we saw how a neural network, for example, is a powerful substrate for learning because, simply by obeying the laws of physics, it can rearrange itself to get better and better at implementing desired computations. Now we’re asking an additional question: What makes a blob of matter able to have a subjective experience? In other words, under what conditions will a blob of matter be able to do these four things? remember compute learn experience

As we’ve seen, physics describes patterns in spacetime that correspond to particles moving around. If the particle arrangements obey certain principles, they give rise to emergent phenomena that are pretty independent of the particle substrate, and have a totally different feel to them. A great example of this is information processing, in computronium. But we’ve now taken this idea to another level: If the information processing itself obeys certain principles, it can give rise to the higher-level emergent phenomenon that we call consciousness. This places your conscious experience not one but two levels up from the matter. No wonder your mind feels non-physical!

Some people tell me that they find causality degrading, that it makes their thought processes meaningless and that it renders them “mere” machines. I find such negativity absurd and unwarranted. First of all, there’s nothing “mere” about human brains, which, as far as I’m concerned, are the most amazingly sophisticated physical objects in our known Universe. Second, what alternative would they prefer? Don’t they want it to be their own thought processes (the computations performed by their brains) that make their decisions? Their subjective experience of free will is simply how their computations feel from inside: they don’t know the outcome of a computation until they’ve finished it.

But let’s not let those controversies distract us from the elephant in the room: there can be no positive experiences if there are no experiences at all, that is, if there’s no consciousness. In other words, without consciousness, there can be no happiness, goodness, beauty, meaning or purpose—just an astronomical waste of space. This implies that when people ask about the meaning of life as if it were the job of our cosmos to give meaning to our existence, they’re getting it backward: It’s not our Universe giving meaning to conscious beings, but conscious beings giving meaning to our Universe. So the very first goal on our wish list for the future should be retaining (and hopefully expanding) biological and/or artificial consciousness in our cosmos, rather than driving it extinct. If we succeed in this endeavor, then how will we humans feel about coexisting with ever smarter machines? Does the seemingly inexorable rise of artificial intelligence bother you and if so, why? In chapter 3, we saw how it should be relatively easy for AI-powered technology to satisfy our basic needs such as security and income as long as the political will to do so exists.

Traditionally, we humans have often founded our self-worth on the idea of human exceptionalism: the conviction that we’re the smartest entities on the planet and therefore unique and superior. The rise of AI will force us to abandon this and become more humble. But perhaps that’s something we should do anyway: after all, clinging to hubristic notions of superiority over others (individuals, ethnic groups, species and so on) has caused awful problems in the past, and may be an idea ready for retirement.

The saddest aspect of life right now is that science gathers knowledge faster than society gathers wisdom. Isaac Asimov

Ever since I learned about the nuclear arms race at age fourteen, I’ve been concerned that the power of our technology was growing faster than the wisdom with which we manage it. I therefore decided to sneak a chapter about this challenge into my first book, Our Mathematical Universe, even though the rest of it was primarily about physics. I made a New Year’s resolution for 2014 that I was no longer allowed to complain about anything without putting some serious thought into what I could personally do about it, and I kept my pledge during my book tour that January: Meia and I did lots of brainstorming about starting some sort of nonprofit organization focused on improving the future of life through technological stewardship.

I finally got to meet Elon in person for further planning when he came to MIT two months later for a space symposium. It felt very strange to be alone with him in a small green room just moments after he’d enraptured over a thousand MIT students like a rock star, but after a few minutes, all I could think of was our joint project. I instantly liked him. He radiated sincerity, and I was inspired by how much he cared about the long-term future of humanity—and how he audaciously turned his aspiration into actions. He wanted humanity to explore and settle our Universe, so he started a space company. He wanted sustainable energy, so he started a solar company and an electric-car company. Tall, handsome, eloquent and incredibly knowledgeable, it was easy to understand why people listened to him. Unfortunately, this MIT event also taught me how fear-driven and divisive media can be. Elon’s stage performance consisted of an hour of fascinating discussion about space exploration, which I think would have made great TV. At the very end, a student asked him an off-topic question about AI. His answer included the phrase “with artificial intelligence, we are summoning the demon,” which became the only thing that most media reported—and

was very happy that there was such consensus at the meeting that more research was needed for keeping AI beneficial, I said, and that there were so many concrete research directions we could work on right away. But there had been talk of serious risks in this session, I added, so it would be nice to raise our spirits and get into an upbeat mood before heading out to the bar and the conference banquet that had been set up outside. “And I’m therefore giving the microphone to … Elon Musk!” I felt that history was in the making as Elon took the mic and announced that he would donate a large amount of money to AI-safety research. Unsurprisingly, he brought down the house. As planned, he didn’t mention how much, but I knew that it was a cool $10 million, as we’d agreed.

key goal of the Puerto Rico conference had been to mainstream AI-safety research, and it was exhilarating to see this unfold in multiple steps. First there was the meeting itself, where many researchers started feeling comfortable engaging with the topic once they realized that they were part of a growing community of peers. I was deeply touched by encouragement from many participants. For example, Cornell University AI professor Bart Selman emailed me saying, “I’ve honestly never seen a better organized or more exciting and intellectually stimulating scientific meeting.” The next mainstreaming step began on January 11 when Elon tweeted “World’s top artificial intelligence developers sign open letter calling for AI-safety research,”5 linking to a sign-up page that soon racked up over eight thousand signatures, including many of the world’s most prominent AI builders.

The open letter was reported by media around the world in a way that made us grateful that we’d barred journalists from our conference. Although the most alarmist word in the letter was “pitfalls,” it nonetheless triggered headlines such as “Elon Musk and Stephen Hawking Sign Open Letter in Hopes of Preventing Robot Uprising,” illustrated by murderous terminators. Of the hundreds of articles we spotted, our favorite was one mocking the others, writing that “a headline that conjures visions of skeletal androids stomping human skulls underfoot turns complex, transformative technology into a carnival sideshow.”

When we announced the list of winners, it marked the first time that the media response to our activities was fairly nuanced and free of killer-robot pictures. It was finally sinking in that AI safety wasn’t empty talk: there was actual useful work to be done, and lots of great research teams were rolling up their sleeves to join the effort.

Mindful Optimism As I confessed in the opening of this epilogue, I’m feeling more optimistic about the future of life than I have in a long time. I shared my personal story to explain why. My experiences over the past few years have increased my optimism for two separate reasons. First, I’ve witnessed the AI community come together in a remarkable way to constructively take on the challenges ahead, often in collaboration with thinkers from other fields. Elon told me after the Asilomar meeting that he found it amazing how AI safety has gone from a fringe issue to mainstream in only a few years, and I’m just as amazed myself. And now it’s not merely the near-term issues from chapter 3 that are becoming respectable discussion topics, but even superintelligence and existential risk, as in the Asilomar AI Principles. There’s no way that those principles could have been adopted in Puerto Rico two years earlier, where the most scary-sounding word that made it into the open letter was “pitfalls.”

Then there’s what he called “mindful optimism,” which is the expectation that good things will happen if you plan carefully and work hard for them. That’s the kind of optimism I now feel about the future of life.

In other words, one of the best ways for you to improve the future of life is to improve tomorrow. You have power to do so in many ways. Of course you can vote at the ballot box and tell your politicians what you think about education, privacy, lethal autonomous weapons, technological unemployment and other issues. But you also vote every day through what you choose to buy, what news you choose to consume, what you choose to share and what sort of role model you choose to be. Do you want to be someone who interrupts all their conversations by checking their smartphone, or someone who feels empowered by using technology in a planned and deliberate way? Do you want to own your technology or do you want your technology to own you? What do you want it to mean to be human in the age of AI? Please discuss all this with those around you—it’s not only an important conversation, but a fascinating one. We’re the guardians of the future of life now as we shape the age of AI. Although I cried in London, I now feel that there’s nothing inevitable about this future, and I know that it’s much easier to make a difference than I thought. Our future isn’t written in stone and just waiting to happen to us—it’s ours to create. Let’s create an inspiring one together!