. >> sophia rosenfeld, what is the definition of common sense and politics? been a good question to start up with. the one thing we never talk about, but refers to all the time. common sense is supposed to be, at least, the kind of thing you don't have talk about. it's the wisdom everybody has. it the obvious, the self-evident and it's something politicians refer to the. if you ever notice that democrats or republicans love to have a commonsense solution to health care or a commonsense solution to problems in the environment, but nobody ever actually says what is common sense, what would it be. every day, ordinary list i'm kind of reasoning about everyday ordinary matters were supposed to basically agree upon without discussion. >> when did it enter -- that turned into political discourse? >> welcome at the very old term that goes back to aristotle in different forms. the faculty come a brain that starting in the early 18 century, it starts to become a political term and starts to suggest a kind of politics everyone can participate and potentially, a sense th