What is colour and how do we create it in our minds?

This Radiolab‘s podcast explores the correlation, starting with Sir Issac Newton, who poked a knife in his eye to decode the answer, to a sea creature that see’s rainbows in a way beyond what humans can experience, to a woman who see’s thousands of more colours than any one of us. The podcast ends with an age-old question, that, it turns out, never even occurred to most humans until very recently: why is the sky blue?

Listen to it here: