The author writes (12/13/16): "The 1965 paper concerned Plato's use of dreaming and waking as metaphors for various contrasts in different philosophical contexts, and especially for its relevance to the Divided Line and Cave of Republic VI-VII. It was a companion piece to my study of Images in the Republic, published in the Archiv sur Geschichte der Philosophie in 1965, and was originally written with it as part of a single long paper. That 1965 paper dealt with Plato's attacks on images and mimesis, and tried to reconcile them with his own constant use of images, especially in Republic V-VII."
Gallop, David, "The Platonic Dream" (1965). The Society for Ancient Greek Philosophy Newsletter. 35.