Discussion from Quora
(Different from above) Prof. Donald Hoffman – The Case Against Reality .
A professor of cognitive science argues that the world is nothing like the one we experience through our senses.
Evolution has shaped us with perceptions that allow us to survive. They guide adaptive behaviors. But part of that involves hiding from us the stuff we don’t need to know. And that’s pretty much all of reality, whatever reality might be.
Snakes and trains, like the particles of physics, have no objective, observer-independent features
Gefter: I suspect they’re reacting to things like Roger Penrose and Stuart Hameroff’s model, where you still have a physical brain, it’s still sitting in space, but supposedly it’s performing some quantum feat. In contrast, you’re saying, “Look, quantum mechanics is telling us that we have to question the very notions of ‘physical things’ sitting in ‘space.’”
Hoffman: I think that’s absolutely true. The neuroscientists are saying, “We don’t need to invoke those kind of quantum processes, we don’t need quantum wave functions collapsing inside neurons, we can just use classical physics to describe processes in the brain.” I’m emphasizing the larger lesson of quantum mechanics: Neurons, brains, space … these are just symbols we use, they’re not real. It’s not that there’s a classical brain that does some quantum magic. It’s that there’s no brain! Quantum mechanics says that classical objects—including brains—don’t exist. So this is a far more radical claim about the nature of reality and does not involve the brain pulling off some tricky quantum computation. So even Penrose hasn’t taken it far enough. But most of us, you know, we’re born realists. We’re born physicalists. This is a really, really hard one to let go of.
Hoffman: The formal theory of conscious agents I’ve been developing is computationally universal—in that sense, it’s a machine theory. And it’s because the theory is computationally universal that I can get all of cognitive science and neural networks back out of it. Nevertheless, for now I don’t think we are machines—in part because I distinguish between the mathematical representation and the thing being represented. As a conscious realist, I am postulating conscious experiences as ontological primitives, the most basic ingredients of the world. I’m claiming that experiences are the real coin of the realm. The experiences of everyday life—my real feeling of a headache, my real taste of chocolate—that really is the ultimate nature of reality.
Tom McFarlane – The cosmos described by physics, however, is a characterization of only that aspect of reality which is revealed when we look through the lens of discrete mathematical concepts which are all traced back to the primordial act of making a distinction. There is still—lest we forget—that aspect of reality that is not revealed as order. This aspect may be called the complement of the cosmos. Because the cosmos is discrete, this suggests that its complement is a continuum—not the mathematical continuum which has definite structure, but an indefinite continuum, a formless void (i.e., the original meaning of the Greek word chaos) that lacks any order and is thus beyond comprehension in terms of concepts or distinction. Reality in its totality, then, encompasses both the cosmos (order) and its complement (chaos). But, more fundamentally, it is prior to the even distinction between cosmos and chaos, form and formlessness, discrete and continuous. Its ultimate nature is therefore ineffable, beyond the scope of mathematics, physics, and even thought itself, which depends on making distinctions. Insofar as it can be known at all, it must be known through other means.