tragic loss of actor robin williams. taking a look back at some of his memorable moments on screen. >> williams was an accomplished comic, who was capable of very dramatic performances. in "dead poet's society" where he huddled up his students and let them in on a little secret. >> medicine, law, business, engineering, these are noble pursuits, necessary to sustain life. but poetry, beauty, romance, love. these are what we stay alive for. >> and now a tragic line from that iconic scene and a role that inspired a generation of teachers. >> also his unforgettable oscar winning role in "good will hunting" with matt damon talking about the loss of his character's wife. take a look. >> i feel like god put an angel on earth just for you. who could rescue you from the depths of hell. and you wouldn't know what it is like to be her angel, to have that love for her, to be there forever. through anything. through cancer.