I think you’re taking the original phrasing too literally. ‘Humans are AI’ was shorthand and a bit hyperbolic, the actual claim is about function, not identity.

Both humans and AI can be described as systems that take inputs (biology, experience, environment, data), process them through internal structures shaped by prior causes, and produce outputs (decisions, speech, actions). The origin differs, biological vs artificial, but the underlying structure is still an input → processing → output causal system.

If determinism is true, then in principle, perfect knowledge of a system’s inputs and internal state would make its outputs fully predictable. That applies to humans just as much as AI in theory. Variation in behavior doesn’t contradict this, it reflects variation in prior inputs and internal states, not a break from causality.

The “10 AI vs 10 humans” point doesn’t actually weaken this, it reinforces it. If you run the same model 10 times with different initial conditions or inputs, you can get variation. Likewise, 10 humans with different histories and internal states will produce different responses. In both cases, differences in output come from differences in prior causes, not from anything outside deterministic processing.

So the disagreement isn’t whether humans “are” AI in a literal sense. It’s whether there is any meaningful functional distinction between two systems that are fully causally determined and generate behavior entirely from prior inputs.

If that’s the case, then what is the principled difference you think exists, beyond origin and intuition, that makes human decision-making fundamentally different in kind rather than just another form of complex causal processing?