Jamie James in Lapham's Quarterly:
If the paramount project of W. B. Yeats’ professional life was the perfection of the art of poetry, it was intertwined with a personal preoccupation, the study and practice of magic— not in any metaphorical sense, but the dedicated pursuit of supernatural powers based upon the ancient traditions of alchemy and necromancy, which began in his youth and persisted to the end of his long life.
Yeats wrote frankly about his vocation as a magician in several memoirs and in A Vision, a dense astrological treatise he labored over for twenty years. A Protestant Irishman in Victorian Britain, Yeats as a young man was pulled in conflicting directions, but the occult always trumped worldly concerns, because it was so deeply connected with his poetic craft. In 1892, when the Irish patriot John O’Leary admonished the twenty-seven-year-old poet for his devotion to magic at the expense of the Cause, Yeats answered:
Now as to magic. It is surely absurd to hold me “weak” or otherwise because I choose to persist in a study which I decided deliberately four or five years ago to make, next to my poetry, the most important pursuit of my life…If I had not made magic my constant study I could not have written a single word of my Blake book [The Works of William Blake, with Edwin Ellis, 1893], nor would The Countess Kathleen [stage play, 1892] have ever come to exist. The mystical life is the center of all that I do and all that I think and all that I write.
That’s plain speaking, which admits no ambiguity. If one would understand the works of the poet often described as the greatest of his age, it might seem necessary to come to terms with this lifelong passion. Yet apart from the prose works mentioned and a handful of supernatural tales in the vein of Edgar Allan Poe, Yeats never directly addresses the practice of magic in the poetry and plays upon which his magisterial reputation rests. He alluded to it only rarely, with ambiguous metaphors and a select hoard of words charged with esoteric meanings.
Magic imbrued Yeats’ thinking so profoundly that it’s nearly impossible to disentangle the strands without rending the garment.