"Everybody has to solve that "meaning of life" and purpose question for themselves. Everybody does it their own way. I think you have to be thoughtful about the way that you're doing it. So I describe it as purpose. If you can think about leading a purposeful life - not just an accumulation but you actually make the world a better place - then I think in the grand scheme of the universe, that that explains our existence. If not, we're just passing through. We're grains of sand and we're blowing in the breeze."