Your complimentary articles

You’ve read all of your complimentary articles for this month. To have complete access to the thousands of philosophy articles on this site, please

If you are a subscriber please sign in to your account.

To buy or renew a subscription please visit the Shop.

If you are a print subscriber you can contact us to create an online account.

Articles

What Did Mary Know?

Marina Gerner on a thought experiment about consciousness.

Imagine a girl called Mary. She is a brilliant neuroscientist and a world expert on colour vision. But because she grew up entirely in a black and white room, she has never actually seen any colours. Many black and white books and TV programmes have taught her all there is to know about colour vision. Mary knows facts like the structure of our eyes and the exact wavelengths of light that stimulate our retinas when we look at a light blue sky.

…