Many of the ideas of A Vision can distract from the poetry. They may even actually confuse the reading of a poem which is accessible without them. We do not, for example, need to know that the 'wandering gyre' of the falcon's flight in 'The Second Coming' connects with his vision of history, and it could be argued that the connection actually diminishes the power and universality of the poem, making it a smaller, more thesis-ridden work than it is without this knowledge. Likewise, in 'Sailing to Byzantium' the phrase 'perne in a gyre' is perhaps the only major flaw in the poem, bringing in an extraneous and unnecessary complication to a poem, bringing in an extraneous and unnecessary complication to a poem otherwise transparent. (A 'perne' can be both a bobbin and a peregrine falcon; here, to complicate interpretation further, it could be either noun or verb.)
It is only in its large sweep that Yeats's philosophy is necessary to understand the poetry. In the poem, 'The Gyres', for example, we need to know only its barest outlines. The title invokes his most notorious concept (usually pronounced with a hard 'g'). The poem can be very simply paraphrased: an old man, facing death, takes a kind of heady consolation from the fact that all things pass and come around again, and delights in charting the details of the modern disintegration. Even though itself, we are told, gets worn out. Beauty and worth outlive themselves; 'ancient lineaments' (the lines of a face, with the hint perhaps of a family lineage preserved by family features) suffer extinction.
The present age (the late 1930s), the poem suggests, is a time of such extinction on a large scale. The blood-dimmed tide of 'The Second Coming' has been released on the earth. By a kind of transference, the ancient Greek philosopher Empedocles (who believed all things are a mingling of the four elements, held together by love or separated by strife, perpetually entering into new configurations) is held responsible for the present disorderliness in things. Another Troy is about to burn, like all those old civilizations put to the sword in 'Lapis Lazuli'. But 'what does it matter?' Yeats asks. All that we need to do is ' "Rejoice!" ' This poem is a powerful expression of Yeats's delight in an apocalyptic view of things.
'Old Rocky Face' in the 'The Gyres' represents that supernatural world beyond history, from which, Yeats's mysticism, all true meaning derive. In 'The Man and the Echo' it becomes 'Rocky Voice'. This poem however implies that the supernatural voice of the oracle is only the echo of human explanations, projected onto the abyss and coming back to us as divine wisdom. Yet significantly, though the Voice reiterates the man's words with the instructions 'Lie down and die' and 'Into the night', it does not echo as a command the last word of his argumentative and unanswered question: 'Shall we in that great night rejoice?'
By contrast, 'The Gyres' suggests that the only attitude to take towards all this tumult is to 'laugh in tragic joy', accept and rejoice in whatever is coming, and stand above it. This is the posture taken by the Hamlet and Lear of 'Lapis Lazuli', who embrace 'Tragedy wrought to its uttermost' with a 'Gaiety transfiguring all that dread'. For, as Yeats says there:
All things fall are built again,
and those that build them again are gay.
The recurrence of all things links these poems with the poem Yeats chose to make the vehicle of his own epitaph, 'Under Ben Bulben'. Here again he tells us, speaking of the eternal return, that 'Gyres run on'. In 'The Gyres' recurrence is enacted by the way in which the word 'gyres' returns at the end, having been exclaimed twice at the very beginning of the poem, confirming stylistically what it claims as a truth, that 'all things [will] run/On that unfashionable gyre again'. But what are these 'gyres'?
In A Vision Yeats conceived of history as composed of two cones, rotating in opposite directions, the apex of each at the centre of the other's widest arc.Every moment in time moves through these opposing spirals. Any one moment thus contains two antithetical, interpenetrating movements, for one cone is widening as the other, whirling in the opposite direction, narrows. These spiraling motions are the gyres. The times of maximum historical turbulence are those where the gyres reverse their motions. These great historical reversals occur every cycle of two thousand years (the 'Great Year'), at those moments where previously expanding cone begins to contract and the previously contracting cone to expand.
Throughout history, the interpretation of the gyres means that one dominant historical principle, the primary phase, is always shadowed by its antithesis, the objective by the subjective, and vice versa. The rape of Leda by a god in the shape of a swan is thus reversed in the annunciation of the dove to Mary. Christ, as the male god of love, reverses the female bringer of strife, Helen. In turn, these phases of the Great Year are reproduced in the twenty-eight 'Phases of the Moon', set out in Yeats's poem of that name, and explained at length in A Vision.
Before the full moon of history, the subjective principle holds sway, and men seek fulfillment in themselves, in mastery of thought and action. After the full, men turn outwards, towards the objective world, before which they shrink in servitude, as in our own era. But the complete darkness without any moon of the twenty-eight phase, that of complete objectivity, brings a reversal, a movement back to subjectivity. It is in the movement between these antithetical gyres that human history and personal life are shaped.
In some of the later poems, a knowledge of the philosophy certainly helps to elucidate what is otherwise obscure in poems which get a great deal of their power from the esoteric doctrine they propound. But most of Yeats's poetry can be approached without worrying too much about this doctrine. For those who are interested in the philosophy, however, the clearest exposition and analysis is probably that of Northrop Frye, in An Honoured Guest. In this book, he explains: "The human soul is always moving outward into the objective world or inward into itself; and this movement is double because the human soul would not be conscious were it not suspended between contraries, the greater the contrast the more intense the consciousness. The man, in whom the movement inward is stronger than the movement outward, the man who sees all reflected within himself, the subjective man, reaches the narrow end of a gyre at death, for death is always, they contend, even when it seems the result of accident, preceded by an intensification of the subjective life; and has a monument of revelation immediately after death, a revelation which they describe as his being carried into the presence of all his dead kindred, a moment whose objectivity is exactly equal to the subjectivity of death. The objective man on the other hand, whose gyre moves outward, receives at this moment the revelation, not of himself seen from within, for that is impossible to objective man, but of himself as if he were somebody else. This view is true also of history, for the end of an age, which always receives the revelation of the character of the next age, is represented by the coming of one gyre to its place of greatest expansion and of the other to that of its greatest contraction. At the present moment the life gyre is sweeping outward, unlike that before the birth of Christ which was narrowing, and has almost reached its greatest expansion. The revelation which approaches will however take its character from the contrary movement of the interior gyre. All our scientific, democratic, fact-accumulating heterogeneous civilization belongs to the outward gyre and prepares not the continuance of itself but the revelation as in a lightning flash, though in a flash that will not strike only in one place, and will for a time be constantly repeated, of the civilization that must slowly take its place. This is too simple a statement, for much detail is possible.