For the ears, you can listen to an audio recording of this presentation. [high fidelity audio playable under all personal computer operating systems via VLC media player, Microsoft Windows Media Player with the Xiph.org codecs for FLAC et al, OS X QuickTime with the XiphQT plugin, etc., on many Android-based mobile devices, and on iOS-based mobile devices via apps such as FLAC Player or Golden Ear]

While listening to this presentation and discussion you may contemplate an image (similar to the copy held up at the front of the classroom) of the fresco painting The Resurrection by Piero della Francesca (circa 1463-1465).