Comment by ozy | Hacker News Reader

Comment by ozy | Hacker News Reader

Amazing talk.

"Markov Decision Model ... also called a story" :)

As for consciousness, I like his explanation. I personally think it is the brain that keeps a log of past decisions, so that when pain/pleasure comes, it can look back and see what decision to reward/punish (delayed reinforcement based learning). The moment a brain puts higher level things in decisions, like expectation of pain/pleasure, and even "I made a decision", is when self awareness comes in.

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I disagree somewhat when he says reality looks nothing like what our brain thinks reality looks like. With different sensors, sure it would all look very different. But not like reality is a cellular automata, and our sensors register that stuff raw, yet our brains imagine (dream) the patterns as objects and people with colors and sounds.

Our sensors see by the laws of physics, seeing objects with properties made possible by the laws of physics. That underlying those laws might be something entirely different, perhaps. But the translation from that underlying thing happened before the light hit your eye, not in the brain. E.g. color is a property of reality, not of the brain.

A completely different effect is that the "picture" we are get in our brain, is heavily pre processed and filtered and predicted. So the color that we notice, and what light has hit our eyes, those are not the same.

Would be interesting to know what he ment by that.

> E.g. color is a property of reality, not of the brain.

Reality simply provides a field that vibrates at different wavelengths and it is intelligence and evolution that come up with computationally convenient category boundaries along that spectrum. We are certainly unaware of many things that are part of the universe without the help of tools.

I agree that we can be certain that when e.g. we see a large rock falling, that our mental representations relate with 99.999% certainty to the event actually occurring. There are however many things which are more subtle, and I think this is what he was referring to.

Right - what is 'brown' after all? There's no such single wavelength. Its a mental fudge when multiple wavelengths are present, and can be any of several different patterns that are quite distinct but perceived as the same thing.

"There are however many things which are more subtle, and I think this is what he was referring to."

Can you give an example? Because I cannot think of any.

That we interpret the wavelength, or even the combination of wavelengths, to mean to us, say brown. Sure. But knowing how the brain does that, we can easily predict what things look brown to us and why. Including when something is brown (physically), but looks red to us, because it is surrounded by something our brains would think is a shadow, so it compensates.

We don't directly perceive of the phenomenon of EM radiation, but rather only perceive a superficial, low-resolution projection of what is actually going on.

There are many things that are too small, too large, too fast or too slow etc. for us to notice. For example, you miss out all the air eddies you create as you move through the atmosphere. Lots of things are also simply out of sight and our minds construct perhaps 50% of what we perceive by pattern completion. I think what we perceive is mostly right, but in many ways it only corresponds superficially to the computations that are actually going on.

I don't find this distinction very useful either though. Yes, there is an illusion of confidence in the accuracy of what we experience, and a lot of it is tainted by values and false memories, but still, it seems plausible that our experiences correspond very directly to things happening in the universe.

I also don't agree with the claim that mathematics being real in a Platonic sense is an illusion. It all comes down to how you define 'real'. I find a sensible definition is that it is a thought that corresponds to how the world works, to things in the world (future, present or past), but also to how the world hypothetically, but very plausibly works. In the same way as you can plausibly assume that any imaginable thought corresponds to something in a remote region of an infinite universe (or multiverse), you can also assume that our mathematical theorems correspond to some computation somewhere. It makes sense to extend the definition of real by immediacy: The fictitious novel is also real (in some multiverse), but it does not have as much immediate real-ness as mathematics. For mathematics you can find all kinds of correspondences in nature (e.g. 1+1=2), but in the novel you can mostly only find things you've previously taken from nature to write the novel, but if your predictions are very real, then it might at some point be impossible to tell whether it is true or not (just like a computer game that almost looks real).

We perceive a low resolution, small slice, of reality, which our brains preprocess and amend by prediction, and that is "what we see". So yes, we don't see anything outside that resolution, or outside of that small slice. And there is some real warping going on when the brain recognizes faces, eyes, mouths. Or shadows, perspective, the horizon.

But I don't think that is what Joscha Bach was talking about. He said reality is very different from the dreamed up reality our brains present to us.

The only thing I can come up with is "disgust". If somebody with dirty hands touches something else, that other thing is now tainted in your mind, and the brain is pretty good at tracking what is tainted. Even if it has no physical counterpart.

Something similar for ownership. In a way, things in reality are recognized and tagged with extra information, dirty, owner, important ... etc.

Something similar for math, or money, stealing, or how society works. Yet I think most of us can easily recognize that those things are not part of reality, but part of structure humans put on top of reality to analyze it, or to share ideas about it, and work together in it.

But what idea in the mind is so far away from its counterpart in reality, that one could say the mind dreams it up? Or has no counterpart, yet the brain thinks it has. Maybe agency when we do not know the agent?

Just watched all his 4 talks https://media.ccc.de/search?q=Joscha . Time well spend on this Sunday January first :) And if I interpret it correctly, he is talking about concepts that come not from our direct sensors, but from structures humans put on top of reality, because things mean something to us.

That makes sense. I also enjoyed the previous three talks a lot, but he should really write it all down.

And to add to the Markov Decision Model: strategies to the decentralized partially observable markov decision process (dec-pomdp) is a model for our shared strategies in spoken and non-spoken communication (grounding.).

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