Some of my favorite commenters were puzzled by my post of the End of History.

Quick notes for those who haven’t followed me all the way on

this multi-year journey

1) The End of History is the notion popularized by Francis Fukuyama that Democratic-Republicanism is the ultimate form of government and that it will be universal in the near future. This represents the End of History in that our basic struggle over political structure of society will be settled.

People push back on this notion on multiple fronts but the front I push hardest on is that Democratic-Republicanism is not likely to be the optimal form of government in the future. Rather than the End of History we are in an odd phase defined by the explosive growth and extensive biological and cultural diversity among humans.  These things are likely to come to an end and produce a society that is stable and has no use for democracy.

2) The second issue which is what the title of this post speaks to, is about how long we expect the human project to go on.

Putting probabilities on our extinction is a hard. However, there are several lines of reasoning that suggest it might not be too far off. The simplest goes like this. If we extrapolate what seems to be clearly possible in terms of economic growth, peace and prosperity generally in the world, then we get a global economy growing at at least 2% per capita for several hundred years.

At that point space travel becomes relatively cheap and I don’t want to go into a lot of detail here but there is strong reason to believe that at least some group of humans will want to devote themselves to space travel and exploration.

Those humans will search out new worlds and come to cover a large portion of our visible universe.

Here is the problem. From the beginning of humanity until this scenario plays out is not very long. This suggests that once sentient life gets started its pretty easy to go out along this path.

So the question is: can we really be the first? Why isn’t our portion of the universe already filled with explorers?

One possible answer is that the process of getting to exploration involves developing technologies that ultimately lead to the destruction of the potential explorers. Its not hard to see what these techs might be: Unfriendly AI, uncontrolled nanotech, highly developed chemical or biological weapons in the hands of terrorists, etc.

Thus, it might be the case that increasing technological sophistication is ultimately self-extincting because the probability of an extinction level mistake becomes very high when your technological sophistication becomes very high.

This is the Great Filter that prevents our universe from being filled with explorers and is why we don’t see any explorers right now. Since no one else has made it past this hurdle its unlikely that we will either. We would have to “beat the odds” as it were.

Another possibility is that the universe is filled with explorers but they are purposefully hiding from us, hoping that we never actually make it off of earth. If we do make it off of earth there is reason to believe they would destroy us. I won’t go deep into that here, but I think the case for destroying potentially rival civilizations is pretty strong.

3) Malthusian stagnation. So the idea, which I feel pretty confident in, is that eventually stagnation will set back in. This is not because we will exhaust all of earth’s resources or something like that. While that could happen I don’t think of it as a serious possibility.

Instead the fundamental problem is that the “Grid of Reality” is discrete and bounded and therefore finite. That is, there are minimum sized particles that interact at minimum distances. Add, to that the fact that at any moment our descendents are bound in a finite region of space by our light cone.

This implies that we are dealing with a finite number of possible configurations of reality. Once, we have mastered the ability to manipulate those configurations there is literally nowhere else to grow.

That is, the possibilities for growth are literally not limitless because there are not an unlimited number of possible configurations for our portion of the universe to be in.

No matter how large that number is – and it is of course very large – a growing economy will hit the max at some point in the future. Thus growth simply cannot be forever.

Thus, even if you could overcome basic entropy problems you still run into the fact that exponential growth means that at some time T we will have mastered all of the configurations within our light cone and we would have to cross the light cone to continue at an exponential pace.  This is impossible.

Knowing this, it becomes the case that each of our decedents at some point will only be able to exercise command over some subset of possible configurations at the expense of some other descendent having command over that subset. This sets up the fundamental Malthusian tension.

Now, it is likely the case that we will hit practical constraints before we hit this “ultimate constraint”, however, knowing that there is an ultimate constraint tells us that no amount of technological progress, innovation or ingenious breakthrough can produce indefinite growth.