Chapter Three – The Spark

This long and varied chapter has so much material it could be a book itself, and it almost is. The chapter centers on two misconceptions, called The Principle of Mediocrity and Spaceship Earth.

I love the discussion of the Spaceship Earth misconception. I’ve been bothered for a long time about the almost mystical reverence people seem to hold for the environment. The reality is that nature is harsh. Unless we save ourselves, the environment will eventually wipe our species from the universe. This is exactly what has happened to the overwhelming majority of species that have ever arisen on the planet. To believe that we are somehow different, unless we make ourselves different, is magical, wishful thinking.

On the other hand, Deutsch’s attack on the Principle of Mediocrity originally left me cold. No, I’m not so concerned with the idea that our place in the universe is special. Sure it’s special. We live on a rare planet in a rare solar system. We live in gravitational and magnetic fields that are both rare and unique. We live near a stable, solitary star in a system with stable, circular orbits. There’s lots about our situation that is far from typical. Of course we’re special. If we weren’t, we wouldn’t be here.

What actually got me was Deutsch’s swipe at Richard Dawkins – specifically Dawkins’ idea that, since our brains evolved in a particular environment for particular purposes, there’s no intrinsic reason to suppose that we should be able to understand everything about the universe. In JBS Haldane’s phrase, “The universe is not only queerer than we suppose, it is queerer than we can suppose.”

Our brains, in this view, are no different from our thumbs, our stomachs, or our eyes. They are parochial adaptations to our environment. But Deutsch makes the convincing argument that this cannot be the case. I think he’s convinced me, and I suspect that he might even convince Dawkins were the two to discuss it.

His argument comes down to this. We know that all possible transformations of material in the universe come in two classes:

1) Those transformations forbidden by the laws of physics – for instance, an object at location “a” cannot move to location “b,” one light year from “a,” in less than one year.

2) Those transformations not forbidden by the laws of physics – for instance, moving an object from “a” to “b” in one year or greater. Any such transformation requires only the knowledge to make it happen. If the transformation wasn’t possible, then there would be a law of physics preventing the transformation.

Note that Deutsch doesn’t claim that humans won’t gain more knowledge. Far from it. Instead, he says that we already have the ability to gather all the knowledge available. In other words, any other people (defined as universal explainers, and therefore universal constructors) we might ever encounter (or build, as in artificial intelligence) will be like us. While they might well have knowledge that we lack, they won’t be qualitatively different kinds of thinkers.

I’m still struggling with this idea. Wouldn’t any advanced race naturally believe that they’d advanced as far as there was to go? But Deutsch’s argument is very subtle. He’s not saying we’ve advanced as far as we can (or will), only that in order to keep advancing we don’t need any ability that we don’t already have. We are already universal explainers, and all universal explainers must be the same.

Deutsch then uses some of his most inspirational language to show the true power of explanatory knowledge. Just one example is supernovae. We observe supernovae all through the universe, and we have very good explanations of how and why they happen. But these explanations make a tacit assumption that there aren’t intelligent beings out there, making transformations that alter the rate of supernovae. Only intelligent beings could do so, and since anything not ruled impossible by the laws of physics must be possible given the right knowledge, it must be possible to alter the rate of supernovae explosions. We could alter that rate. We could alter anything about the universe that we choose to alter. We could be the spark that causes the universe to behave in a new way. If it isn’t impossible, then with the right knowledge we could choose to make it so.