Ceilings and Horizons

Why human ideas have unbounded reach and genes don’t

I’m rereading The Beginning of Infinity, a book of powerful ideas by David Deutsch. One of my favourite sections explains how knowledge is created by comparing biological evolution with human cultural evolution. I think this is probably the only place where I’ve come across a thoughtful, sophisticated discussion of what cultural evolution is, one that reaches deep below the surface.

To begin with, evolution by high-fidelity replication requires two components: variation and selection.

1. Variation in genetic knowledge is randomly generated, whereas variation in human conjectures is creatively generated.

2. Genetic knowledge has limited, non-explanatory reach, whereas human conjectures and explanations can have unbounded reach.

It turns out that 1) is the cause of 2).

This means that anything that blocks human knowledge from being unbounded can only be either one of two things: the laws of physics and nature, which are impossible to break, or self-imposed, self-limiting ideas, which are possible to break.

In terms of how this maps back to the two components of evolution, it means that any limit on human knowledge arises not from evolution’s variation component (creativity), but its selection component (criticism). Therefore, human knowledge’s reach is limited only by our own bad choices to stop criticising any inferior ideas, thereby masking the benefits of better ones.

Because we are human, we have this deep desire to create knowledge. Our creativity engines never switch off. So open, dynamic societies strive to unchain the selection component (criticism). Closed, static societies, however they choose to suppress criticism, always relentlessly attack the variation component (creativity) in order to live to fight another day.

We see the unmistakeable effects of this in history. The attitude of fragile, static societies towards human knowledge resembles the violence of biological evolution. Static societies will kill people in order to stop them from killing bad ideas. However, dynamic societies will kill bad ideas in order to stop them from killing people.

The thing is, a static society is doomed no matter what choices it makes. If it succeeds in its mission to block the creation of new ideas, it will fall to unforeseen problems because its institutions will not be able to solve them fast enough, especially with such limited knowledge. If a static society fails in its mission to block the creation of new ideas, it will be doomed because new ideas will replace the ancient, static ones, and it will no longer be the same as before.

When it comes to biological evolution, no matter how well natural selection corrects for reproductive design, the knowledge in genes faces a permanent ceiling by evolution’s variation component: random mutations to knowledge.

But when it comes to human cultural evolution, no matter how hard we try to kill our natural desire to be creative, the knowledge in human ideas faces, at the most, a temporary ceiling, only by our bad choices to disable evolution’s selection component: criticism.

This has overturned how I see human history, from merely being a series of events after another, to an ongoing, forever battle between problems and the ideas created to address them.