Scared of superintelligent AI? You should be, says neuroscientist and philosopher Sam Harris — and not just in some theoretical, existential crisis kind of way. We’re going to build superhuman machines, says Harris, but we haven’t yet grappled with the problems associated with creating something that may treat us the way we treat ants.

Why do we dance? African-American social dances started as a way for enslaved Africans to keep cultural traditions alive and retain a sense of inner freedom. They remain an affirmation of identity and independence. In this electric demonstration, packed with live performances, choreographer, educator and TED Fellow Camille A. Brown explores what happens when communities let loose and express themselves by dancing together.