[Erica Sadun, Sean Hillyard, Pam Korda, Leigh Butler]
The Aelfinn and Eelfinn (henceforth referred to as "the Finn") are strange tricksy critters who live in other dimensions. They are also known as the Snakes and Foxes, because of their appearances, and have long-standing tricksy relationships with humans: giving gifts and answers... at a price.
Most of what we know about the Finn is from TSR. There is also a little bit in the Guide, and scant but telling information is gained in WH.
[TSR: 6, Doorways, 95] and [TSR: 15, Into the Doorway, 174-180]:
[TSR: 24, Rhuidean, 278-282] and [TSR: 26, The Dedicated, 306-307]:
[TSR: 28, To the Tower of Ghenjei, 323-324]:
[Guide: 3, The Age of Legends, 33]:
[WH: 31, What the Aelfinn Said, 588] and [WH: 35, With The Choedan Kal, 649]:
Cyndane's info, in particular, has sparked speculation on how exactly this coexistence works. Perhaps the game of Snakes and Foxes that Mat and Olver play may yield a clue as to how Aelfinnland and Eelfinnland are linked.
From [LOC: 33, Courage to Strengthen, 456], the game board is described as "a piece of red cloth with the web of lines drawn in black ink, and arrows showing which lines allowed movement only one way and which both." Sketchy, but the phrase "the web of lines" implies that the pattern may be like an actual web - straight spokes overlaid with either concentric circles or a spiral.
Interesting, since the architecture of the Snakes' domain is described as all curves and spirals [TSR: 15, Into the Doorway, 174-176], and everything in Foxland is sharp straight angles and polygons; the most often-recurring shape in the Foxy architecture is an eight-pointed star [TSR: 24, Rhuidean, 279-281]. Perhaps something like the spokes of a web with the circles taken away?
Given all this, Gabriel Wright theorizes that perhaps the game played in the real world actually accurately depicts Finnland; the Aelfinn (Snakes) live in the spiral part of the web, while the Eelfinn (Foxes) live on the spokes. Separate, but linked. There's definitely a certain elegance to the idea.
Mr. Wright also observes that there may be a link between the "snaring" purpose of the snake and fox tokens in the game and Birgitte's warning to Perrin about entering Finnland through the Tower of Ghenjei. Perhaps people coming in illegitimately (i.e., not through the twisted doorways) free the Finn from their age-old treaty, making the intruders fair game for capture?
As additional food for thought on the composition of Finnland: there are windows to whatever passes for outside in Finnland in the Snaky place (which is where Mat sees the three curved silvery spires over and over). However, the only openings in Foxland are to the inside, showing the chamber Mat entered from over and over again.
In that vein, Paul Ward received a letter from RJ in March 2000 in which RJ said (answering a question about why the Fox doorway melted in TFOH): "When Moiraine and Lanfear went through the ter'angreal, it burned in part because both were channeling, and the world on the other side of the doorway has a radically different set of natural laws. The odd optical effects witnessed in that other world are not artificially produced artifacts."
Interesting. It does make a certain amount of sense, as John Novak points out, that Finnland must have "a radically different geometry, which is definitely sufficient to produce the optical effects seen, [and that this would also] screw up what seems to be a geometrically based system of magic - weaves must almost certainly depend on geometry, from the way they're described."
This does raise the question of how Rand managed to not only channel in Snakeland, but actually step from one world to another while holding the weave. Without knowing more about how exactly the physics of Finnland differs from Randland's, the best explanation anyone can come up with to explain this is that at that point in the series, Rand hadn't had any real training in wielding the OP; he was doing everything by instinct. So he did what felt right in the real world, and did what felt right in Finnland. As for stepping from one reality to another... One other suggestion is that perhaps the fact that Rand was wielding Fire had something to do with why the Finnland physics didn't screw him up, since they are vulnerable to fire.
And on that note, isn't it remarkable that Aludra - and her matches - are now travelling with Mat and Thom? Just in time for a rescue, perhaps? [Erica Sadun]
During a ride with Tuon, Mat becomes overwhelmed with the memories of another time and begins to speculate on how these memories were collected in the first place. [KOD 8: Dragon Eggs]
Maybe they created some sort of link to any human that visited them, a link that allowed them to copy all of a man's memories after that right up to the moment he died. In some of those memories from other men, he was white=haired, in some only a few years older than he really was, and everything in between, but there were none of childhood or growing up.
Later on his comments make it seem as if he believes the Finns might be seeing events through his eyes as he experiences them. Might this be the reason for Egwene's Dream of "Mat throwing dice with blood streaming down his face, the wide brim of his hat pulled low so she could not see his wound, while Thom Merrilin put his hand into a fire to draw out the small blue stone that now dangled on Moiraine's forehead." If the second part represents Thom rescuing Moraine from Finnland, then what does the first part mean? It's been speculated by many that Mat may try to gain advantage over the Finns by putting out one of his eyes.