At 2024's Manifest, Robin Hanson gave a talk (in his usual sweeping polymathic style) on cultural drift - a phenomenon for which he thinks "there's going to be hell to pay", and about which he is "scared, because this is a really big fundamental problem".

Watch the recording of the 30:00 minute talk here (followed by Q&A).

His argument is roughly the following:

• Evolution between species is more important (more adaptive) than evolution within species.
• The same is true of cultural evolution.
• In the last couple hundred years, there has been a great reduction of evolution between cultures. There are now far fewer cultures, and all of the changes are happening within these cultures.
• There is less famine and war now, i.e. much less selection pressure.
• Therefore, our cultural changes are not adaptive - they're not responsive to selection pressures. They're "drifting off the rails" (hence cultural drift).
• Dropping fertility rates are a consequence of this drift: "I interpret this [dropping fertility] as our main macro-world culture becoming less adaptive..."

Hanson takes this cultural drift to be a problem. But here I become confused. From what perspective is cultural drift a problem? The obvious candidate is the POV of our culture - if it is not adaptive, it will likely die out. We don't want our culture to die out. But Hanson seems to want to appeal to a perspective outside of our culture:

• "There are two levels of thinking about culture, one is from the inside and one is from the outside. I'm trying to get you to see it from the outside..."
• "I'm here scared, because this is a really big fundamental problem. This is Humanity's main engine..."

It seems Hanson wants to say that this is a problem for Humanity, not just for our culture. However, cultures dying out and being replaced by more adaptive ones is exactly what we would expect of a healthy evolutionary system. If our liberal western culture (whatever that means) goes extinct and is replaced by the Amish or Mennonite cultures (as Hanson suggests it might), then this looks like selection working "as intended".

Despite Hanson saying that we should see things "from the outside", all of the specific worries he cites are quite clearly from inside our culture:

• "We would then plausibly have several centuries of a declining population with very little innovation."
• "...the world will become less liberal."
• "the Amish and Mennonites are doubling every twenty years, will just keep doubling, and in a few centuries come to dominate... Humanity doesn't go extinct there... It's not that terrible - it's not existential... It's pretty bad though, several centuries decline of our civilization, loss of liberality"
• "...a lot of what we create here will be lost... our civilization and the precious things we are creating and collecting much of that may be thrown away"

I agree these are all bad things. I like technology. I like Liberalism. But if Hanson's whole argument is simply: "if our culture goes away, that's bad!" then why did we need the framework of cultural evolution, the "outside perspective", and so on? Why not just say: "Our fertility is dropping, and illiberal cultures' fertility is rising. If this stays the same, our culture will be overtaken by illiberal ones. That's bad!" ? This way of putting it gets at the exact same worry in a more direct way.

So, maybe I don't understand Hanson's argument. Curious to hear others' thoughts.