Cited by Walter Pater, Studies in the History of the Rennaissance. 1873.
Description:

'Enthusiasm—that, in the broad Platonic sense of the Phaedrus, was the secret of his divinatory power over the Hellenic world. This enthusiasm, dependent as it is to a great degree on bodily temperament, gathering into itself the stress of the nerves and the heat of the blood, has a power of reinforcing the purer emotions of the intellect with an almost physical excitement.' (93)

'To the unprogressive ritual element it brought these conceptions, itself the pterou dunamis, [trans. in later editions: 'the power of the wing'] an element of refinement, of ascension, with the promise of an endless destiny.' (100)