Neil Mann interprets:
Since it affects the poetry more obviously and more directly than almost any other part of the System, the view of history proposed in A Vision has received more critical attention than any other area, not all of it entirely accurate. The basic principles are, however, relatively easy to grasp, and Yeats himself noted that the section treating history, ‘Dove or Swan’ (AV A Book III and AV B Book V), was among the more accessible parts of A Vision.
The title ‘Dove or Swan’ alludes to a particularly potent yoking of ideas through symbol. The Archangel Gabriel’s annunciation to the Virgin Mary is often accompanied in art by a descending dove to symbolise the angel’s message that she would conceive a child: ‘The Holy Ghost shall come upon thee, and the power of the Highest shall overshadow thee: therefore also that holy thing which shall be born of thee shall be called the Son of God’ (Luke 1:35).