'This attachment - essentially a romantic attachment, of the Ireland that Yeats envisaged is not co-extensive with the real Ireland of small farms and small towns but a doorway on the world of Faery - turned him into a polemicist. One of the characteristics of the Nineties movement that he noted in his early Autobiographies was the indifference of the pre-Raphaelites and their followers to generalisations - yet generalisations was Yeats strongest suit. He was a born argufier, equally about nationality, and ethics, and aesthetics. He resolved this contradiction thus. [q.p.]
Pater supplied Yeats with a belief in the importance of passion, a belief in the importance of style, a distrust of the vulgar world, and a curious sort of aesthetic pantheism ... .
'[...] in his love poetry Yeats repeatedly deplores his beloveds refusal to observe the rules of the game, to content herself with existing merely as a beautiful object. Throughout his life his advice to women is to abjure the intellect and, in particular, political opinions and the critical reason. Their discipline is to be that of the looking glass. 
Some of Yeats later strong ideas: To me drama ... has been the search for more of manful energy, more of cheerful acceptance of whatever arises out of the logic of events, and for clean outline, instead of those outlines of lyric poetry that are blurred with desire and vague regret.
'Surely the ideal of culture expressed by Pater can only create feminine souls.
'Yeats had previously been fascinated by the Irish peasant because he was a person who knew the fairies. It was Synge who brought home to him the value of this brute vitality, of, in Yeatss words all that has edge, all that is salt in the mouth, all that is rough in the hand, all that heightens the emotions by contest, all that stings into life the sense of tragedy. ... From time of meeting Synge, Yeatss poetry shows far more recognition of physical man. .
Yeats began by ignoring the Godwin and Rousseau and the Plato in Shelley; in his essay on the Philosophy of Shelleys Poetry (1900) he spends his time discussing Shelleys symbols - caves, underground rivers, towers, the morning star - and attempts to build out of these a Shelleyan system ... 
McNeice: the kind of nationalism which he admired, represented by John OLeary was in decline. The nationalism dominant seemed to him to involve a shocking waste of energy and to have ruined the lives of a number of his friends. It was vulgar .... 
Yeats wrote in 1925 that when he had been young, his Muse had been old; as he himself grew older, his Muse grew younger. [58; Warner var. 55.]
Yeats praised bad Irish poets in his articles for the Boston Pilot and Providence Sunday Journal , 1887-89, from your Celt in London; in these articles he made painstaking efforts to discover talent, if not genius, in contemporary Irish writers such as Ellen OLeary and Rose Kavanagh. He could even bring himself to admire a poem by the former which ends And oh, my darling, I am true / To God - to Ireland - and to you. Again, he laments that T. W. Rolleston would not canalise his writing into national channels: He is a fine Greek scholar and quite the handsomest man in Ireland, but I wish he would devote his imagination to some national purpose. Cosmopolitan literature is, at best, but a poor bubble, though a big one. Creative work has always a fatherland. 
Yeatss attitude to Maud Gonne [who could only express her personality through violence as Florence Farr could only express it through an unfashionable art] seems always to have had something about it of odi atque amo. He could never quite forgive her die-hard opinions and her violence; at the same time her influence saved him fro being merely a poet of the salon or the psaltery. 
Yeats would not have come into being without Rossetti. 
[Yeats] wrote in the Boston Pilot that it is necessary really to know the imaginative periods of Irish history [introduced by Standish OGrady] Yeats, however, failed to do justice to the imaginative periods of Irish history because he emasculated them, just as Tennyson had emasculated Lancelot and Gawaine ... Yeats in old age himself ... explains in a footnote [the phrase great bladdered Emer]: The Irish sagas have a hard matter-of-factness ... A woman of divine origin was murdered by jealous rivals because she made the deepest hole in the snow with her urine. 
The legends which he selected in early days were those which presented escape from the ancient heroic world itself ... Niamh calling: Away, come away: / Empty your heart of its mortal dream.
[H]e craved for a mythology which would be for him what the Virgin Mary and Veronica with her napkin are for the Catholic Irish peasantry ... he found in Celtic legend what Johnson and Dowson found in Catholic ritual; Celtic legend had the advantage of not having been recently exploited.; ... There is no absolute recipe for poetry. 
[On Green Helmet and Other Poems:] [O]n the whole the sheen and mystery are gone; statement predominates over suggestion. The mood is consistently depressed, his hopes both of love and Ireland have reached a low ebb. He is working out a manner which is flat and at the same time distinguished. In 1909, Yeats was complaining in his diary of Irelands soullessness: Irish is ruined by abstractions ... ill-breeding of the mind ... every thought made in some manufactory and with the mark upon it of its wholesale origin. ... I did not see until Synge began to write that we must renounce the deliberate creation of a kind of Holy City in the imagination, and express the individual. 
Yeatss cult of the Big House is to be correlated with his dislike for democracy, liberalism, the facile concept of progress.
[On Yeatsian opposites:] [I]n fighting for a political creed one is following a mythic archetype; in sexual love one is tuning to the music of the spheres.
Yeats had an epigrammatist in him who hardly showed in the early poetry 
Eternity; he quoted from Blake, is in love with the productions of time; or, in the words of an Irish peasant which he was fond of repeating, God possesses the heavens - but he covets the earth. 
Yeatsian opposites: in fighting for a political creed one is following a mythic archetype; in sexual love one is tuning to the music of the spheres.; Now, however, he was on the whole an accepter of life instead of a rejecter of it, and one can see the influence of Synge ... 
Yeats had an epigrammatist in him who hardly showed in the early poetry 
1916 gave Yeats a shock ... at once enlivening and horrifying. He had built an Ireland out of words and now he saw them translated into action.
Yeats in his poems treated Synge and major Robert Gregory in the same way that Shakespeare treated his tragic heroes and heroines; the hero is conceded full individuality, his Marxist conditioning is ignored. This means simplification, ... it means the elimination from the tragic figure of all psychology except some simple trends, it means the explanation of a man by his daily life but my one or two great moments ... His characters are simplified into bold symbolical figures; all Synges significance is for Yeats summed up on the line - dying chose the living world for text. 
[On A Vision:] He recounts that when his wife began transmitting the messages ... he made them an offer that he would spend the rest of his life explaining and piecing together those scattered sentences. No, was the answer, we have come to give you metaphors for poetry. Spirits had taken the place of Standish OGrady. 
A large section of A Vision consists of the classification of human types. Yeats disregards psychology as much as he disregards economics. According to his friends he was a poor judge of men ... Lacking intuitive knowledge of people he declined also to accept explanations offered by professional psychologists ... If life is to be conditioned by accidents, the accidents must be supernatural. [Quotes Yeats:] When I think of any great poetical writer ... I comprehend, if I know the lineaments of his life, that the work is the mans flight from his entire horoscope, his struggle in the networks of the stars ( Per Amica Silentia Lunae). This principle, of a man desiring his opposite, is worked out in detail in A Vision. 
Quotes Yeats: Some people will ask whether I believe in the actual existence of my circuits of sun and moon ... I regard them as stylistic arrangements of experience comparable to the cubes in the drawing of Wyndham Lewis and the ovoids in the sculpture of Brancusi. they have helped me to hold in a single thought reality and justice.(A Vision, 1925 edn.) 
[On 1916 Rising:] his attitude is slightly patronising and at the same time envious. 
Further, MacNeice spoke of Yeatss exemplification of the clannish obsession with ones own family; the combination of an anarchist individualism with puritanical taboos and inhibitions; the half-envious contempt for England; the constant desire to show off; a sentimental attitude to Irish history; a callous indifference to those outside the gates; an identification of Ireland with the spirit and England with crass materialism. (Q. source.)