Anil Seth

In physics and in philosophy, determinism is the proposal that all events in the universe are completely determined by previously existing physical causes.

colour is the place where our brain and the universe meet

When I look at a red chair, the redness I experience depends both on properties of the chair and on properties of my brain. It corresponds to the content of a set of perceptual predictions about the ways in which a specific kind of surface reflects light. There is no redness-as-such in the world or in the brain.

You could even say that we’re all hallucinating all the time. It’s just that when we agree about our hallucinations, that’s what we call reality.

The fact that people have such different experiences and report them with such confidence, for the very same image, is compelling
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evidence that our perceptual experiences of the world are internal constructions, shaped by the idiosyncrasies of our personal biology and history. Most of the time, we assume that we each see the world in roughly the same way, and most of the time perhaps we do. But even if this is so, it isn’t because red chairs really are red, it’s because it takes an unusual situation like The Dress to tease apart the fine differences in how our brains settle on their perceptual best guesses.

Once seen, it is hard to unsee

Nothing in what I say should be taken to deny the existence of things in the world, be they onrushing trains or cats or coffee cups. The ‘control’ in controlled hallucination is just as important as the ‘hallucination’. Describing perception this way doesn’t mean that anything goes, it means that the way in which things in the world appear in perceptual experience is a construction of the brain.

We do not see things as they are, we see them as we are.

res cogitans (mind stuff) and res extensa (matter stuff).

The most fundamental reason any organism has a brain – or any kind of nervous system – is to help it stay alive, through making sure that its physiological essential variables remain within the tight ranges compatible with its continued survival.