I am Yuval Noah Harari. I'm a historian and professor in the Department of History at the Hebrew University of Jerusalem. I'm the author of the popular science bestsellers Sapiens: A Brief History of Humankind (2014), Homo Deus: A Brief History of Tomorrow (2016), and 21 Lessons for the 21st Century (2018). my writings examine free will, consciousness, intelligence, happiness, and suffering.