Younger brother of the more famous
苏秦 (Sū Qín). Both were
纵横家 (zònghéngjiā), itinerant strategists who shuttled between kingdoms. Su Dai is the source of the
鹬蚌相争,
渔翁得利 ('snipe and clam fight, fisherman benefits') parable, recorded in 《
战国策》 (Strategies of the Warring States).