but Ray's right that the brain cannot be more complex than the data that specifies it, speaking information-theoretically.
You're conflating two very different concepts of complexity here.
One is the complexity of a static state of information, and the other is the complexity arising from dynamical systems.
As roadnottaken pointed out, fractals are perfect examples of systems that are described by very "simple" formulas, yet contain infinite complexity. It could therefore be said that the simple equation of the Mandelbrot set represents infinite complexity.
However, if you take a particular iteration of the formula, then you can get a finite concept of its complexity, i.e. how many bits it takes to represent the image you're seeing.
So, to say that the "the brain cannot be more complex than the data that specifies it" is true in one sense, but completely useless in another.
To put this into terms of the Mandelbrot, you can gather up all the bits that represents some particular iteration of the Mandelbrot, but that doesn't tell you anything about how it works, or even how to generate the next frame. You need the equation for that.
That's just one place where Ray fails. The second is the lingering question of whether computers in their current state are even capable of "simulating" a brain. It's still not an answered question of what the role of the non-determinism found in Quantum Mechanics plays in the brain and the interactions of various chemicals. It was recently shown that DNA relies on QM entanglement to "hold it together". If it turns out that non-determinism and QM effects play a crucial role in biology (which they almost certainly do), then the very rigid and deterministic system that is the CPU may simply be incapable of simulating a human brain.
The objective is to simulate the real-time activities of the brain, not the evolutionary-time activities that were and are acting on the brain.
Continuing from your extension of the fractal analogy, the former is more like an "iteration of the Mandelbrot" while the latter is "how to generate the next frame".
We do not need to know how our human-precursor brains worked, nor do we need to know what our human-successor brains will be like to successfully simulate current-human-brain intelligence.
It seems plausible to me that we will be able to understand how to simulate the functions of the brain without necessarily simulating the physical universe and its remarkable evolutionary unfolding--which seems to be the ultimate level of complexity and one that I agree is far beyond us.
You're conflating two very different concepts of complexity here.
One is the complexity of a static state of information, and the other is the complexity arising from dynamical systems.
As roadnottaken pointed out, fractals are perfect examples of systems that are described by very "simple" formulas, yet contain infinite complexity. It could therefore be said that the simple equation of the Mandelbrot set represents infinite complexity.
However, if you take a particular iteration of the formula, then you can get a finite concept of its complexity, i.e. how many bits it takes to represent the image you're seeing.
So, to say that the "the brain cannot be more complex than the data that specifies it" is true in one sense, but completely useless in another.
To put this into terms of the Mandelbrot, you can gather up all the bits that represents some particular iteration of the Mandelbrot, but that doesn't tell you anything about how it works, or even how to generate the next frame. You need the equation for that.
That's just one place where Ray fails. The second is the lingering question of whether computers in their current state are even capable of "simulating" a brain. It's still not an answered question of what the role of the non-determinism found in Quantum Mechanics plays in the brain and the interactions of various chemicals. It was recently shown that DNA relies on QM entanglement to "hold it together". If it turns out that non-determinism and QM effects play a crucial role in biology (which they almost certainly do), then the very rigid and deterministic system that is the CPU may simply be incapable of simulating a human brain.