Pictures made with egg tempura and gold leaf glitter, but they cannot represent light and darkness. Program Three, The Conquest of Light, looks at Jan van Eyck"s Arnolfini Marriage and how the advance of oil paint allowed artists to represent earthly reality. Program Four, From Illusion to Emotion reveals how, as artists became more skilled in the use of oil, they began to picture not only objects, but states of mind and emotions. Caravaggio"s Supper at Emmaus and Rubens" Samson and Delilah help demonstrate the power of the artist to engage the viewer.