I think Hoffman makes some fundamental errors when he discusses evolution and cognition. He says that evolution doesn’t evolve us to perceive “the truth” but rather evolved us to only perceive what will help us adapt.
His first error is to think that this is some major revelation. It's not. In fact people like Dawkins and Robert Trivers have written at length about how (even though at first it seems counter intuitive) organisms can evolve to deceive themselves or otherwise have less than perfect knowledge about the external world. The most obvious example is in kin recognition. It is a much more harmful error (in the sense of reproductive success) for a mother to fail to recognize her child than to make the reverse error. Hence most females are tuned to recognize an organism as her child even when there seems to be strong evidence against that fact. Birds like the cuckoo take advantage of this bias by laying their eggs in the nests of other birds. Even though the cuckoo baby often looks nothing at all like the other actual children the mother bird will usually adopt the cuckoo as her own, even when the Cuckoo is much larger than her adopted siblings and is taking far more than a fair share of the food.
There are many other examples. Trivers has an excellent book on the subject called The Folly of Fools: the logic of human self deception.
Hoffman’s second error is that he doesn’t understand that while it is correct that organisms didn’t evolve to have optimal information of the external world the kinds of errors that they make are mostly understandable and predictable. He speaks as if the rational conclusion of the fact that we don’t have optimal knowledge is to just say that all knowledge is suspect and should be discarded. That is clearly false. For the majority of possible traits better information equals better adaptation. Predators evolve better sight. Prey evolve better hearing.
Indeed the optical illusions Hoffman starts his talk with are excellent examples that show that humans can understand and correct for the errors that evolution has saddled us with. Theories such as Evo-Devo as well as the standard Darwinian model of adaptation provide us with good models to explain and predict where imperfect knowledge will likely occur due to constraints on possible designs (the vertebrate eye example) or the adaptive advantages of imperfect knowledge (the cuckoo example).
The proper response to these issues is not to just assume that all existing information is wrong but rather to continue to try and understand why and where we may have errors in our perception and cognition.
What I found even more puzzling was that after saying that we have to throw out all of existing science and concepts such as causality, Hoffman then proceeds to talk about causality and things like Markhov processes in regard to his new model. If causality is totally invalid then its as invalid in some new model as it is in existing models. If the external world and traditional math and physics are all an illusion then so is the science and math that assume there is an outside world which gave us things like Markhov models and quantum physics.
I will say that I think this topic is extremely interesting. For example, I think we can make a good case that the basic foundations for math as well as concepts such as causality and morality are innate cognitive mechanisms. This leaves open the question: could we even know if there are alternative ways of conceiving the world? My suspicion is that the reason these mechanisms are innate is that they correspond to some universal truths about how the universe is organized and can be understood. I think it is a completely unjustified leap to go from the fact that there are minor and understandable biases in our faculties of understanding to the conclusion that we should completely discount them.
I shall begin by springing to the defence of Hoffman's honour and saying that I'm sure he doesn't think he's showing anyone optical illusions for the first time, and I think he's reminding people of the fact of top-down perception, rather than trying to astonish them with the concept. However, where his conception is at least somewhat novel is the degree to which he is proposing this is so.
ReplyDeleteI say it is somewhat novel, because similar suggestions have been made before - but by people like Siddhartha Gautama and Rene Descartes rather than Richard Dawkins or Robert Trivers. He's not saying that our senses are fallible, but that they are fallacy.
On your second point, I don't get the impression that he is suggesting that the logical conclusion of optical illusions is that nothing is real. He is putting this forward, I feel, as a possible direction rather than a conclusion. In Hoffman's universe, eagles can evolve sharper and sharper vision, and this is clearly beneficial for them, but it does not mean that they are seeing what is really there. To use his desktop analogy, they simply upgraded to a retina display.
Nor do I see that he is saying that we need to throw out all of science - indeed, he is trying to derive all of science from his model. I cannot comment as yet on his maths, as I have not looked at this yet and anyway maths has a lot of work to do before it becomes my strong point. But he certainly is not claiming to have come up with a new physics - but an alternative way of deriving the old physics. An alternative, that is, to materialism.
If I had to summarise Hoffman's ideas succinctly, I would say that he is trying to provide a mathematical proof for Buddhism. Not the whole of Buddhism, but least the part of it that deals with the nature of the material world.
"He's not saying that our senses are fallible, but that they are fallacy"
DeleteBut my point is that his argument doesn't support that. His argument only shows that our senses are fallible (can sometimes be wrong) not fallacy (completely untrustworthy). I think where he goes wrong is he holds up "the truth" as if it is an all or nothing proposition.
He seems to me to be saying that since we sometimes can't trust our senses they don't give us "the truth" and therefor we can't trust them at all (they are fallacy).
I think that is a completely unwarranted leap. Also, if our senses really ARE a complete fallacy then don't we have to throw out ALL of science? I mean if the external world is really just an illusion than how can we really know anything and why should we consider deriving quantum physics as an achievement since it is a result of a science that assumes the external world we perceive through our flawed senses is real?
If he was starting off from a computational neuroscientific standpoint, looking at optical illusions and then declaring that nothing was real, then I would have to agree with you that it is a bit of a leap.
ReplyDeleteBut Hoffman isn't David Marr. He's not interested in explaining optical illusions and sensory faculties. I think that the optical illusion thing is just an introduction and explanation of his 'desktop' metaphor of sensory reality. And this metaphor is in turn an explanation of how physical reality could be derived from a consciousness-first model. And it is consciousness that he is attempting to explain, or if not explain then at least grasp. So he's not making any big leaps, because the consciousness-first perspective is his point of departure.
Physics wouldn't need to be thrown out - it would still be valid and just as much a part of reality as anything else. It would just be subsumed in a wider framework. Maybe trying to subsume physics is arrogant, but maybe he just thinks well what the hell... you only live once.
I know he's going out on a limb, you know he is, and so does he. But this consciousness thing is damned illusive and I agree with him that we need to try some radical shit on it. You and I have different opinions on the matter of consciousness. Personally, given the evidence, I think there's a 49% chance that we live in a physical world, a 49% chance we live in a metaphysical world, and a 1% chance that something different and super-freaky is going on that we haven't even thought of. Those figures don't quite add up, but when you're talking about consciousness, what does?