Renowned theoretical physicist Stephen Hawking, who examined the universe and helped to explain black holes, died yesterday at the age of 76. While his family hasn't given an official cause of death yet, Hawking has suffered from ALS since the age of 21. ALS paralyzed him, and eventually he could only communicate using a cheek muscle attached to a speech-generating device.
Back in 2008, Hawking gave a TED talk where he said that our only chance of long-term survival was to spread out into space. In the clip below, you can see his incredible mind at work, his sense of humor, his optimism and his humility. Hawking even said that his disease made him lucky because he had more time to pursue the quest for knowledge.
You can watch Hawking's incredible mind at work in the clip below.