Anil Seth

The sense of personal identity, built on the narrative self, can erode or disappear entirely in dementia and in severe cases of amnesia, and it can be warped and distorted in cases of delirium, whether hospital-induced or not.

The self is not an immutable entity that lurks behind the windows of the eyes, looking out into the world and controlling the body as a pilot controls a plane.

The experience of being me, or of being you, is a perception itself – or better, a collection of perceptions – a tightly woven bundle of neurally encoded predictions geared towards keeping your body alive. And this, I believe, is all we need to be, to be who we are.

the brain is a ‘prediction machine’, and that what we see, hear, and feel is nothing more than the brain’s ‘best guess’ of the causes of its sensory inputs.

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