W. B. Yeats's poetry is associated in many readers’ minds with dreams, and these figure in some of his bestremembered lines, such as “Tread softly because you tread on my dreams” or “In dreams begins responsibility.” Poems that do not explicitly mention dreams often evoke an oneiric atmosphere, from the dim grey sands of Rosses Point to the fiery pavements of Byzantium, and throughout Yeats's creative career many of his greatest poems take place in a visionary realm. Indeed, although Yeats's understanding of the nature of sleep and dream changed through the course of his life, their importance is a consistent thread in his thought and work.

Sleep and dream are an essential part of poetic heritage too, whether the dream poems of the Middle Ages and Renaissance or the Romantic worlds created by Coleridge, Shelley, and Keats. Though the insistent presence and use of dreams in Yeats's work are striking, readers still generally view his preoccupation with dream within the context of this tradition, heightened by Celtic twilight, Pre–Raphaelite vagueness, and folkloric flight into fairyland.

Such factors are certainly an influence, but it is easy to overlook his very particular approach to and understanding of dream: for Yeats the phrases quoted above are not just evocative images or a way affirming pursuit of heartfelt aspirations. When, in “He Wishes for the Cloths of Heaven,” the poet speaks of wishing he had cloths embroidered “with golden and silver light” (VP176; CW170) but of having instead only dreams to spread under his beloved's feet, most readers find both metaphors poignant and convincing. Yet, alone at night, Yeats used a range of techniques— meditative, magical, and auto–hypnotic—in order to meet Maud Gonne in dream, weaving evocations of gold and silver rings, jewels and starlight. He was convinced that they were truly meeting in some non–physical realm, in spirit, and he was effectively laying his dream–life at her feet. In February 1903, Gonne trod rough–shod over those dreams—in both mystical and colloquial senses—by announcing her engagement to John MacBride. Yeats justified remonstrating with her by referring to a dream vision of hers from 1898, in which they had been married by the Irish sun god, Lug (CL3315; G–YL164), and asserting the rights that this gave him and the duty he felt.