Author of Being You: A New Science of Consciousness
Co-director of the Sackler Centre for Consciousness Science · Canadian Institute for Advanced Research Program on Brain, Mind & Consciousness

This is a point in philosophy that the world as it is can never be directly apprehended by our minds. We are shielded from it by what's called a sensory veil. There are, for instance, no such thing as colors that are out there. As the artist Cezanne said, "The colors are where the brain and the universe meet." And color is, I think, a really good example because it is, in a sense, less than what's there because our eyes are only sensitive to three wavelengths of this huge electromagnetic spectrum, which goes all the way from x-rays and gamma rays to radio waves. And we live in a tiny, thin slice of that reality. But then out of those three wavelengths we experience our brains generate many more than three colors and almost an infinite palette of colors. So there's no sense in which our perception could ever reveal the world as it really is, that it reveals the world in a way that's very useful for us as organisms hell-bent on continuing to live and to survive.