>> fred: yes >> seth: this is edgar degas' 1872 painting "dance class at the opera. >> fred: oh, yes painter wanted to be in the painting okay >> seth: oh. >> fred: so you see that there's a chair there. he was supposed to be facing the camera, or the canvas, as it were - [ light laughter ] -- in that chair and so - >> seth: do a lot of -- do a lot of art historians make that canvas/camera mistake? >> fred: it's so common that we have an inside joke. we call the canvas "the camera." and we just all kind of laugh as historians like, "i know what you mean. >> seth: yeah, yeah. >> fred: so we -- so the painter, degas, kept running to -- he kept running to that chair. and he thought he'd run fast, you know, back fast enough that he'd be able to paint himself. and what's -- what's really nice about it is, first of all, he drove the dancers crazy, 'cause they're like, "are you ever going to get this? we're in this position." and he's like, "just keep warming up and we're going to get this." so that's what you're seeing here is he thought he would be able to do it. every time he sat back do