It may have been the dream of Martin Luther King, Jr. that all of us be judged on the content of our character. But, what if the content of our character doesn't count for much? Tufts psychologist Sam Sommers contends that who we are may be less important than where we are in his new book, "Situations Matter." He finds context – not personality – governs the decisions we make, from the profession we choose to the people we fall in love with. Sam Sommers spoke to Madeleine from his home in Boston.