I'm close to the same. I can function on 7, but any less than that and I'm a basketcase, and really do honestly need 8 a day. I feel like people think it's a virtue or something if they can get 4 hrs of sleep and not fall down from exhaustion, but in reality it's so unhealthy.

I'm sure he and a lot of other people would rather accomplish certain things in their life even if it means dying an early death, as opposed to living a long life that doesn't satisfy them.

I realize that it's not always that cleanly zero sum, and yes, it's definitely possible to live a life that is both full and long, but in the case of Musk and perhaps others who put their heart and soul in their companies (especially during the early period), it's not so clearcut.