Arthur Dénouveaux was among the crowd of Parisians listening to music at the Bataclan concert hall in 2015 when ISIS extremists burst into the hall and started shooting into the crowd. This week, Salah Abdeslam, the lone survivor among the assailants, was found guilty of murder. Dénouveaux talks with The World’s host Marco Werman about the verdict and his efforts to make sense of the tragic events.