Steps Up The Ladder

While not all change has been positive, there is one big way in which humanity has “progressed” over the long run — we have grown vastly more capable, able to support a larger population, and recently a larger economy.

How far have we come, and how far might we go? Imagine this progress as climbing a ladder on the side of a tall building, where at each new floor we get ten times more capable. If floors are ten feet apart, and ladder steps are one foot apart, then each ladder step represents a decibel of growth, i.e., a factor of 1.26.

From a population of perhaps a thousand folks two million years ago, humanity has so far climbed about nine floors, or 87 steps, up the ladder. We climbed 36 steps as foragers, taking fifty millennia per step, 23 steps as farmers, taking three centuries per step, and so far 28 steps as industrialists, taking five years per step. (All estimates rough.) How much further might we climb?

An em civilization might climb even faster, at least for a while, taking a step per day! A few months ago I estimated population sizes for very advanced em civilizations:

[Using] android ems … a two kilometer deep Earth city could hold a … thousand billion billion ems. And a solar system civilization might fit a billion billion billion ems.

Reaching this last level would require us to climb about fifteen more stories, or 150 steps. And since the observable universe contains a thousand billion billion stars, to reach a universe-spanning civilization with this density we’d need to climb an additional twenty-one stories, or 210 steps. So, we’ve climbed nine floors as humans, but have perhaps another thirty six floors to go, to reach the “top” forty-fifth floor. That’s four times as far to go as we have come.

Yes, we might find ways to grow more after that, and our pre-human ancestors must have also done a lot of growing. But my main point is that we hope to climb much further than we have climbed so far.

What more can we say about this future climb? Our biggest fear should be falling off the ladder to the ground below, never to rise again. To avoid such a fall we must find the right tradeoff between climbing slower to carefully inspect each new step, and climbing faster to avoid the hailstones, wind gusts, etc. that we expect from time to time, and which we expect are less problematic further up.

Of course we should also wonder what we may become as we rise. We are no longer the foragers who began this climb, nor the farmers who climbed just a few floors below, and those ancestors would probably not be pleased with everything we have become. We’ll probably also have misgivings about what our descendants become. But hopefully we will on net be proud of them, just as our ancestors would probably be proud of us.

Attempts to see more clearly up the ladder tend to fall to two extremes. Many folks study trends over the last few steps, and tentatively conclude that such trends may continue for another few steps. And many such folks also declare it to be impossible, as a matter of principle, to see further. They often respond to concrete arguments about more distant forecasts with “that must be wrong, since we can’t see that far,” as if that were some sort of law of physics.

At the other extreme, some folks claim to see all the way to the ladder’s top. We’ve been getting less fertile and more green, rich, peaceful lately, so very advanced civilizations must be idle rich zero-population-growth leave-nature-be peaceniks. Or we’ve been getting more into movies and video games lately, and like fast net connections, so very advanced civilizations must be virtual reality navel-gazers crushed into tiny balls. Or because an AI might improve itself, one AI will soon take over the world and then live on forever as indisputable ruler of the universe.

Now I do suspect that a few of the basic physics limits we now see apply to our universe’s true physics, of which the physics we see is only an approximation. For example, if light speed and entropy limits persist, then growth and innovation must eventually slow way way down. And evolutionary theory seems robust enough to embolden me to estimate that in the absence of strong central coordination, competition must force our descendants to be well adapted to their environments, in an evolutionary sense.

But I don’t yet see how to say much more about the very long run. That isn’t impossible, but it does seem very hard. So I prefer to focus on trying to see into the next era, beyond our industry era. While that does take more than a simple projection of current industry-era trends, it takes far less than is needed to see life in the very distant future, way up on floor forty and beyond. To see into the next era one needs only good general theories about how societies work, and a good guess regarding the key changes by which the next era will differ from ours.

We can imagine progress as climbing a ladder on the side of a tall building, where at each new floor we get ten times more capable, and each one-foot-apart ladder step represents a decibel of growth. We’ve climbed through three or so floors of foraging, two and a bit of farming, and may climb through three to six floors of industry, before coming to a new era, which may last through two to seven more floors. It seems to me that at least some of us should try to use our best social science and guesses on the biggest upcoming changes to try to understand this next post-industry era, even if we don’t know how to envision the five to ten or more eras which may follow after.