What If We Had Bigger Brains? Imagining Minds Beyond Ours

Summary

Cats Don’t Talk We humans have perhaps 100 billion neurons in our brains. But what if we had many more? Or what if the AIs we built effectively had many more? What kinds of things might then become possible? At 100 billion neurons, we know, for example, that compositional language of the kind we humans use is possible. At the 100 million or so neurons of a cat, it doesn’t seem to be. But what would become possible with 100 trillion neurons? And is it even something we could imagine understanding? My purpose here is to start exploring such questions, informed by what we’ve seen in recent years in neural nets and LLMs, as well as by what we now know about the fundamental nature of computation, and about neuroscience and the operation of actual brains (like the one that’s writing this, imaged here): One suggestive point is that as artificial neural nets have gotten bigger, they seem to have successively passed a sequence of thresholds in capability: So what’s next? No doubt there’ll be things like humanoid robotic control that have close analogs in what we humans already do. But what if we go far beyond the ~1014 connections that our human brains have? What qualitatively new kinds of capabilities might there then be? If this was about “computation in general” then there wouldn’t really be much to talk about. The Principle of Computational Equivalence implies that beyond some low threshold computational systems can generically produce behavior that corresponds to computation that’s as sophisticated as it can ever be. And indeed that’s the kind of thing we see both in lots of abstract settings, and in the natural world. But the point here is that we’re not dealing with “computation in general”. We’re dealing with the kinds of computations that brains fundamentally do. And the essence of these seems to have to do with taking in large amounts of sensory data and then coming up with what amount to decisions about what to do next. It’s not obvious that there’d be any reasona...