Daniel Lemire's blog

, 6 min read

Foolish enough to leave important tasks to a mere human brain?

To the ancient Greeks, the male reproductive organ was mysterious. They had this organ that can expand suddenly, then provide the seed of life itself. Today, much of biology remains uncatalogued and mysterious, but the male reproductive organ is now fairly boring. We know that it can be cut (by angry wives) and sewed back in place, apparently with no loss of function. As for providing the seed of life, artificial insemination is routine both in animals (e.g., cows) and human beings. In fact, by techniques such a cloning, we can create animals, and probably even human beings, with no male ever involved.

If we go back barely more than a century, flight was mysterious. Birds looked slightly magical. Then a couple of bicycle repairmen, who dropped out of high school, built the first airplane. Today, I would not think twice about embarking in a plane, with hundred of other people, and fly over the ocean in a few hours… something no bird could ever do.

This is a recurring phenomenon: we view something as magical, and then it becomes a boring mechanism that students learn in textbooks. I call it the biological-supremacy myth: we tend to overestimate the complexity of anything biology can do… until we find a way to do it ourselves.

Though there is still much we do not know about even the simplest functions of our body, the grand mystery remains our brain. And just like before, people fall prey to the biological-supremacy myth. Our brains are viewed as mythical organs that are orders of magnitude more complex than anything human beings could create in this century or the next.

We spend a great deal of time studying the brain, benchmarking the brain, in almost obsessive ways. Our kids spend two decades being tested, retested, trained, retrained… often for the sole purpose of determining the value of the brain. Can’t learn calculus very well? Your brain must not be very smart. Can’t learn the names of the state capitals? Your brain must be slightly rotten.

In the last few years, troubles have arisen for those who benchmark the brain. I can go to Google and ask, in spoken English, for the names of the state capitals, and it will give them to me, faster than any human being could. If I ask Google “what is the derivative of sin x”, not only does it know the answer, it can also point to complete derivation of the result. To make matters worse, the same tricks work anytime, anywhere, not just when I am at the library or at my desk. It works everywhere I have a smartphone, which is everywhere I might need calculus, for all practical purposes.

What is fascinating is that as we take down the brain from its pedestal, step by step, people remain eager to dismiss everything human-made as massively inferior:

  • “Sure, my phone can translate this Danish writing on the wall for me, but it got the second sentence completely wrong. Where’s your fantastic AI now?”- “Sure, I can go to any computer and ask Google, in spoken English, where Moldova is, and it will tell me better than a human being could… But when I ask it when my favorite rock band was playing again, it cannot figure out what my favorite rock band was. Ah! It is a joke!”

A general objection regarding the brain is that there is so much we do not know. As far as I can tell, we do not know how the brain transforms sounds into words, and words into ideas. We know which regions of the brains are activated, but we do not fully understand how even individual neurons work.

People assume that to surpass nature, we need to fully understand it and to further fully reproduce it. The Wright brothers would have been quite incapable of modeling bird flight, let alone reproduce it. And a Boeing looks like no bird I know… and that’s a good thing… I would hate to travel on top of a giant mechanical bird.

Any programmer will tell you that it can be orders of magnitude easier to reprogram something from scratch, rather than start from spaghetti code that was somehow made to work. We sometimes have a hard time matching nature, not because nature was so incredibly brilliant… but rather because, as an engineer, nature is a terrible hack: no documentation whatsoever, and an “if it works, it is good enough” attitude. This same objection, “there is so much we do not know”, is used everywhere by pessimists. Academics are especially prone to fall back on this objection, because they like to understand… But, of course, all the time, we develop algorithms and medical therapies that work, without understanding everything about the problem. That’s the beautiful thing about the world we live in: we can act upon it in an efficient manner without understanding all of it.

Our puny brains may never understand themselves, but that does make our brain wonderful and mysterious… it is more likely the case that our brains are a hack that works well enough, but that is far from the best way to achieve intelligence.

Another mistake people make is to assume that evolution is an optimization process that optimizes for what we care about as human beings. For centuries, people thought that if we were meant to fly, we would have wings. Evolution did not give us wings, not as a sign that we couldn’t fly… but simply because there was no evolutionary path leading to monkeys with wings.

Similarly, there is no reason to believe that evolution optimized human intelligence. It seems that other human species had larger brains. Our ancestors had larger brains. Several monkeys have photographic memory, much better strength/mass ratios and better reflexes. The human body is nothing special. We are not the strongest, fastest and smartest species to ever roam the Earth. It is likely that we came to dominate the animal kingdom because, as a species, we have a good mix of skills, and as long as we stay in a group, we can take down any other animal because we are expert at social coordination among mammals.

Yes, it is true that evolution benefited from a lot of time… But that’s like asking a programmer to tweak a piece of code randomly until it works. If you give it enough time, the result will work. It might even look good from the outside. But, inside, you have a big pile of spaghetti code. It is patiently tuned code, but still far from optimality from our point of view.

The Wright brothers were initially mocked. This reassured the skeptics that believed that mechanical flight was a heresy. But, soon after, airplanes flew in the first world war.

In 20 years, we will have machines that surpass the human brain in every way that matters to us. It will look nothing like a human brain… probably more like a Google data warehouse at first… And then we will be stuck with the realization that, from our reproductive organs all the way to our brains, we are nothing special.

Many people refuse to believe that we will ever machines that are better than us in every way. And they are right to be scared because once you invent a machine that is smarter than you are, you have no choice: you have to put it in charge.

Human beings know that they are somehow irrelevant in the grand scheme of things. I write this blog post using a brain that consumes maybe 20 to 30 Watts, with the bulk of my neurons actually invested in controlling my body, not thinking abstractly. In a few decades, it will be trivial to outsmart me. And then I will be back to being an old, boring monkey… no longer a representative of the smartest species on Earth.

Of course, just because we do not need the male organ to procreate does not mean that people stop having sex. The birds did not stop flying when we invented the airplane. Television did not mean the end of radio. The Internet does not mean the end of the paper. Hopefully, my species will make use of its brains for many decades, many centuries… but soon enough, it will seem foolish to leave important decisions and tasks to a mere human brain.

Some of this future is already here.