II. His Ruling Symbols from The Philosophy of Shelley’s Poetry in Ideas of Good and Evil by William Butler Yeats.

“Again and again one finds some passing allusion to the cave of man’s mind, or to the caves of his youth, or to the cave of mysteries we enter at death, for to Shelley as to Porphyry it is more than an image of life in the world.” [via]

Consider also:

  1. “It may be that his subconscious life seized upon some passing scene, and moulded it into an ancient symbol without help from anything but that great memory; but so good a Platonist as Shelley could hardly have thought of any cave as a symbol, without thinking of Plato’s cave that was the world; and so good a scholar may well have had Porphyry on ‘the Cave of the Nymphs’ in his mind.”
  2. “often caves are, he says, symbols of ‘all invisible power; because as caves are obscure and dark, so the essence of all these powers is occult,’ and quotes a lost hymn to Apollo to prove that nymphs living in caves fed men ‘from intellectual fountains’; and he contends that fountains and rivers symbolize generation, and that the word nymph ‘is commonly applied to all souls descending into generation,’ and that the two gates of Homer’s cave are the gate of generation and the gate of ascent through death to the gods, the gate of cold and moisture, and the gate of heat and fire.”
  3. “Cythna in the passage where she speaks of making signs ‘a subtle language within language’ on the sand by the ‘fountain’ of sea water in the cave where she is imprisoned, speaks of the ‘cave’ of her mind which gave its secrets to her, and of ‘one mind the type of all’ which is a ‘moveless wave’ reflecting ‘all moveless things that are'”
  4. “he believed inspiration a kind of death; and he could hardly have helped perceiving that an image that has transcended particular time and place becomes a symbol, passes beyond death, as it were, and becomes a living soul.”
  5. “Shelley compares the flowing through our mind of ‘the universe of things,’ which are, he has explained elsewhere, but thoughts, to the flowing of the Arne through the ravine, and compares the unknown sources of our thoughts in some ‘remoter world’ whose ‘gleams’ ‘visit the soul in sleep,’ to Arne’s sources among the glaciers on the mountain heights.”