Here is W. B. Yeats, remembering some of his early experiences with the occult and supernatural. All taken from his The Trembling of the Veil, collected in Autobiographies:

When staying with Hyde in Roscommon, I had driven over to Lough Kay, hoping to find some local memory of the old story of Tumaus Costello, which I was turning into a story now called Proud Costello, Macdermot’s Daughter, and the Bitter Tongue. I was rowed up the lake that I might find the island where he died; I had to find it from Hyde’s account in The Love-Songs of Connaught, for when I asked the boatman, he told the story of Hero and Leander, putting Hero’s house on one island, and Leander’s on another. Presently we stopped to eat our sandwiches at the “Castle Rock,” an island all castle. It was not an old castle, being but the invention of some romantic man, seventy or eighty years ago. The last man who had lived there had been Dr. Hyde’s father, and he had but stayed a fortnight. The Gaelic-speaking men in the district were accustomed, instead of calling some specially useless thing a “white elephant,” to call it “The Castle on the Rock.” The roof was, however, still sound, and the windows unbroken. The situation in the centre of the lake, that has little wood-grown islands, and is surrounded by wood-grown hills, is romantic, and at one end, and perhaps at the other too, there is a stone platform where meditative persons might pace to and fro. I planned a mystical Order which should buy or hire the castle, and keep it as a place where its members could retire for a while for contemplation, and where we might establish mysteries like those of Eleusis and Samothrace; and for ten years to come my most impassioned thought was a vain attempt to find philosophy and to create ritual for that Order. I had an unshakeable conviction, arising how or whence I cannot tell, that invisible gates would open as they opened for Blake, as they opened for Swedenborg, as they opened for Boehme, and that this philosophy would find its manuals of devotion in all imaginative literature, and set before Irishmen for special manual an Irish literature which, though made by many minds, would seem the work of a single mind, and turn our places of beauty or legendary association into holy symbols. I did not think this philosophy would be altogether pagan, for it was plain that its symbols must be selected from all those things that had moved men most during many, mainly Christian, centuries.

I thought that for a time I could rhyme of love, calling it The Rose, because of the Rose’s double meaning; of a fisherman who had “never a crack” in his heart; of an old woman complaining of the idleness of the young, or of some cheerful fiddler, all those things that “popular poets” write of, but that I must some day, on that day when the gates began to open, become difficult or obscure. With a rhythm that still echoed Morris I prayed to the Red Rose, to Intellectual Beauty:

“Come near, come near, come near—ah, leave me still
A little space for the Rose-breath to fill,
Lest I no more hear common things….
But seek alone to hear the strange things said
By God to the bright hearts of those long dead,
And learn to chant a tongue men do not know.”

I do not remember what I meant by “the bright hearts,” but a little later I wrote of Spirits “with mirrors in their hearts.”

My rituals were not to be made deliberately, like a poem, but all got by that method Mathers had explained to me, and with this hope I plunged without a clue into a labyrinth of images, into that labyrinth that we are warned against in those Oracles which antiquity has attributed to Zoroaster, but modern scholarship to some Alexandrian poet. “Stoop not down to the darkly splendid world wherein lieth continually a faithless depth and Hades wrapped in cloud, delighting in unintelligible images.” (204-5)

I found a supporter at Sligo in my elderly uncle, a man of fifty-three or fifty-four, with the habits of a much older man. He had never left the West of Ireland, except for a few days to London every year, and a single fortnight’s voyage to Spain on board a trading schooner, in his boyhood. He was in politics a Unionist and Tory of the most obstinate kind, and knew nothing of Irish literature or history. He was, however, strangely beset by the romance of Ireland, as he discovered it among the people who served him, sailing upon his ships or attending to his horses, and, though narrow and obstinate of opinion, and puritanical in his judgment of life, was perhaps the most tolerant man I have ever known. He never expected anybody to agree with him, and if you did not upset his habits by cheating him over a horse, or by offending his taste, he would think as well of you as he did of other men, and that was not very well; and help you out of any scrape whatever. I was accustomed to people much better read than he, much more liberal-minded, but they had no life but the intellectual life, and if they and I differed, they could not take it lightly, and were often angry, and so for years now I had gone to Sligo, sometimes because I could not afford my Dublin lodging, but most often for freedom and peace. (205-6)

At Sligo we walked twice every day, once after lunch and once after dinner, to the same gate on the road to Knocknarea; and at Rosses Point, to the same rock upon the shore; and as we walked we exchanged those thoughts that never rise before me now without bringing some sight of mountain or of shore. Considering that Mary Battle received our thoughts in sleep, though coarsened or turned to caricature, do not the thoughts of the scholar or the hermit, though they speak no word, or something of their shape and impulse, pass into the general mind? Does not the emotion of some woman of fashion, caught in the subtle torture of self-analysing passion, pass down, although she speak no word, to Joan with her Pot, Jill with her Pail and, it may be, with one knows not what nightmare melancholy to Tom the Fool?

Seeing that a vision could divide itself in divers complementary portions, might not the thought of philosopher or poet or mathematician depend at every moment of its progress upon some complementary thought in minds perhaps at a great distance? Is there nation-wide multiform reverie, every mind passing through a stream of suggestion, and all streams acting and reacting upon one another, no matter how distant the minds, how dumb the lips? A man walked, as it were, casting a shadow, and yet one could never say which was man and which was shadow, or how many the shadows that he cast. Was not a nation, as distinguished from a crowd of chance comers, bound together by these parallel streams or shadows; that Unity of Image, which I sought in national literature, being but an originating symbol?

From the moment when these speculations grew vivid, I had created for myself an intellectual solitude, most arguments that could influence action had lost something of their meaning. How could I judge any scheme of education, or of social reform, when I could not measure what the different classes and occupations contributed to that invisible commerce of reverie and of sleep; and what is luxury and what necessity when a fragment of gold braid, or a flower in the wallpaper may be an originating impulse to revolution or to philosophy? I began to feel myself not only solitary but helpless. (210-211)

I had not taken up these subjects wilfully, nor through love of strangeness, nor love of excitement, nor because I found myself in some experimental circle, but because unaccountable things had happened even in my childhood, and because of an ungovernable craving. When supernatural events begin, a man first doubts his own testimony, but when they repeat themselves again and again, he doubts all human testimony. At least he knows his own bias, and may perhaps allow for it, but how trust historian and psychologist that have for two hundred years ignored in writing of the history of the world, or of the human mind, so momentous a part of human experience? What else had they ignored and distorted? When Mesmerists first travelled about as public entertainers, a favourite trick was to tell a mesmerised man that some letter of the alphabet had ceased to exist, and after that to make him write his name upon the blackboard. Brown, or Jones, or Robinson would become upon the instant, and without any surprise or hesitation, Rown, or Ones, or Obinson.

Was modern civilisation a conspiracy of the sub-conscious? Did we turn away from certain thoughts and things because the Middle Ages lived in terror of the dark, or had some seminal illusion been imposed upon us by beings greater than ourselves for an unknown purpose? Even when no facts of experience were denied, might not what had seemed logical proof be but a mechanism of change, an automatic impulse? Once in London, at a dinner party, where all the guests were intimate friends, I had written upon a piece of paper, “In five minutes York Powell will talk of a burning house,” thrust the paper under my neighbour’s plate, and imagined my fire symbol, and waited in silence. Powell shifted conversation from topic to topic and within the five minutes was describing a fire he had seen as a young man. When Locke’s French translator Coste asked him how, if there were no “innate ideas,” he could explain the skill shown by a bird in making its nest, Locke replied, “I did not write to explain the actions of dumb creatures,” and his translator thought the answer “very good, seeing that he had named his book A Philosophical Essay upon Human Understanding.” Henry More, upon the other hand, considered that the bird’s instinct proved the existence of the Anima Mundi, with its ideas and memories. Did modern enlightenment think with Coste that Locke had the better logic, because it was not free to think otherwise? (210-212)