Faeries belong to another world, one not defined by humans and our social conventions and mores but irrevocably tied to our own nonetheless. Like the worlds of animals, plants, fungi, and the elements themselves, we perpetually live beside - even within - the Otherworld, yet just as with the animal and plant kingdoms (again, note more political terminology applied by humans to non-human Nature) these realms are generally inscrutable to us. They can certainly seem alien to us at times, but flora, fauna, and faery are certainly not alien to this planet.
"Fairyland is a state or condition, realm of place, very much like, if not the same as, that wherein civilized and uncivilized men alike place the souls of the dead, in company with other invisible beings such as gods, daemons, and all sorts of good and bad spirits. Not only do both educated and uneducated Celtic seers so conceive Fairyland, but they go much further, and say that Fairyland actually exists as an invisible world within which the visible world is immersed like an island in an unexplored ocean, and that it is peopled by more species of living beings than this world, because incomparably more vast and varied in its possibilities."
- W.Y. Evans-Wentz in The Fairy Faith in Celtic Countries
"The Underworld is not just under the ground; it is under/within the surface of every leaf, under the surface of every human thought, under the surface of every pool or water, and deep in the infinite heart of even a tiny pebble."
- Robin Artisson in The Witching Way of the Hollow Hill
"The Otherworld begins where this world ends. Tradtionally it is imagined as a parallel society of daimons or animals or the Dead. It can even be adjacent to us, in the forest or wilderness outside the sacred enclosure of the village. It can be underground, or in the sky, or in the west - or even, like the land of the Sidhe, in all of these places. Indeed, 'it may not be far from any of us'. [...] The Otherworld lies, as it were, all around us, at the points where our world ceases. It lies beyond the edge of the maps where 'there be dragons', or below the threshold of consciousness where there be archetypes.[...] The boundaries where this world ends and the Otherworld begins are always shifting - but Nature contains them both."
- Patrick Harpur in The Philosopher's Secret Fire: A History of the Imagination
"Sometimes Faerie is not a country but a shifting light upon the land, a wistful song, a moment in between other moments. Some people have a greater facility for feeling its presence than others. Children see it easily and often. So do the mad. Shamans and visionaries can travel there and back again. So can the artist who humbly gives his life over to mystery."
- Ari Berk in the foreword to Brian Froud's World of Faerie