Dr. Foreman: You figure that anybody that gives a crap about people in Africa must be full of it?
House: Yes. There's an evolutionary imperative why we give a crap about our family and friends. And there's an evolutionary imperative why we don't give a crap about anybody else. If we loved all people indiscriminately, we couldn't function.
Dr. Foreman: Hmmm. So, the great humanitarian's as selfish as the rest of us.
House: Just not as honest about it.