Acclaimed physicist and cosmologist Stephen Hawking says he would contemplate ending his own life through assisted suicide if he ever became too much trouble to care for or if he felt he could no longer live a productive life. "To keep someone alive against their wishes is the ultimate indignity. I would consider assisted suicide only if I were in great pain or felt I had nothing more to contribute but was just a burden to those around me," Hawking told British comedian Dara O’Briain for an upcoming BBC television piece, The Guardian reports.