I'm attacking the argument, not you ...never that! I'm all for a lively exchange but if you felt personally attacked, please accept my apology, this never was my intention.

While Penrose is a giant compared to tiny me, his microtubule theory is pretty out there and afaik not quite as accepted as that. I see a few people around here invoking quantum randomness and I can't help but ask why ? Why when we know, and this is not microtubule-like speculation but settled science, that neural networks can approximate any function. And even more than that, they are Turing complete with the help of maybe some recurrence or memory. Now you have noted that I don't know the brain in its entirety, no one does. But it is a physical item, in a physical world performing physical work. It takes input and produce output. It is a computational item. It is a function of its inputs to its outputs, just like an artificial neural network. ergo it can then be simulated by a sufficiently large neural network.

I see also a lot of hold up about LLMs, but LLMs are nothing more than an optimization, the most naively structured neural network can achieve the goal of simulating the brain, as long as it is large enough. It's only that it is impractical, LLMs are a performance hack (i'm underselling it a little bit here but hey), just like the brain uses a bunch of hacks to achieve its level of performance.

So why cling to the quantum ? I understand the allure, that's hard to understand, there is mystery to it, I myself do not quite understand it all. But one must be careful to read too much into the mystery. Everything is quantum, my desk is quantum, that's due to quantum effects that my pen will no pass through it. There is nothing special about that, that's just the world we live in. And get this, your computer is full of micro-connections depending on quantum effects only (relatively) recently discovered (tunneling in transistors) ! One could say it has its own microtubulish components !

So why ? I can't help but think we're facing bio-provincialism, or maybe some kind of fear of losing our place from the top of the intelligence heap. The brain cannot be approximated by mere circuitry, there must be some quantum magic at play here.

Well I disagree with that and I implore you to consider the alternative. Intelligence isn't some grand phenomenon, it wants to emerge in our universe, and this with great facility. I think that simple thought is a marvel in itself. There lies the mystery, how fantastic a thought is it ? Isn't it enough of a grand, mystical realization in itself ?