Justin Khoo (M.I.T.) invites us to think about conditional sentences ("if P then Q"). Perhaps surprisingly, the question of what these sentences mean has vexed philosophers for thousands of years. In part 2 of the series on conditionals, Justin discusses some of the challenges facing the material conditional theory, picking up where part 1 (http://youtu.be/4Zxp2-_pLCE) left off. Help us caption & translate this video! http://amara.org/v/GnpK/