Excerpt from Preface to The Unicorn from the Stars and Other Plays by William B. Yeats and Lady Gregory (New York: Macmillan, 1908; rpt. as The Unicorn from the Stars, Cathleen ni Houlihan, The Hour-Glass, 1915]).

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[In] Lady Gregory…I discovered…a greater knowledge of the country mind and country speech than anybody I had ever met with, and nothing but a burden of knowledge could keep ‘Cathleen ni Houlihan’ from the clouds. I needed less help for the ‘Hour Glass,’ for the speech there is far from reality, and so the Play is almost wholly mine. When, however, I brought to her the general scheme for the ‘Pot of Broth,’ a little farce which seems rather imitative to-day, though it plays well enough, and of the first version of ‘The Unicorn,’ ‘Where there is Nothing,’ a five-act Play written in a fortnight to save it from a plagiarist, and tried to dictate them, her share grew more and more considerable. She would not allow me to put her name to these Plays, though I have always tried to explain her share in them, but has signed ‘The Unicorn from the Stars,’ which but for a good deal of the general play and a single character and bits of another is wholly hers…

Excerpt from Preface to Plays for an Irish Theatre by W. B. Yeats, with Designs by Gordon Craig (London and Stratford-on-Avon: A. H. Bullen, 1911; rpt. 1913).

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All summer I have been playing with a little model, where there is a scene capable of endless transformation, of the expression of every mood that does not require a photographic reality. Mr. Craig—who has invented all this—has permitted me to set up upon the stage of the Abbey another scene that corresponds to this, in the scale of a foot for an inch, and henceforth I shall be able, by means so simple that one laughs, to lay the events of my plays amid a grandeur like that of Babylon; and where there is neither complexity nor compromise nothing need go wrong, no lamps become suddenly unmasked, no illpainted corner come suddenly into sight.