My advice to an aspiring actor would be to never stop learning or working for what you want. Nothing comes easy ever if you want something you have to work for it. By working for it I mean work on your craft learn from people who have something to teach. It's just like anything else practice makes perfect.
Carl took on the military-industrial complex. He campaigned around the world for an end to the production of weapons of mass destruction. To him it was a perversion of science.