I can't stand it when people say that Jadis represents Satan. It oversimplifies the series, and lessens its poetic impact. Jadis represents coldness and hatred of others. She turns her victims to stone, reminiscent of the way that insensitive people are sometimes described as having "hearts of stone."

The Green Lady represents darkness and hatred of self. I didn't completely understand this as a child, I just knew that she was a lot scarier than Jadis. When I re-read the book as an adult, having had a friend who struggled with major depression, the book took on whole new meaning. I know some Narnia fans would consider this silly psycho-babble, but when you've been close to someone with major depression, the resemblance between the effects of the Green Lady's magic and the symptoms of depression really strikes you between the eyes. It also stands to reason that someone who experienced as much loss as Lewis had would know about these things, even if he wasn't familiar with clinical definitions.

I had never really thought of the LOTGK in that manner before, Anhun. . . but you are absolutely correct. She really is a manifestation of depression. She dwells in the dark, and takes years from Rillian's life, keeping him trapped in his own mind. . .

Hmm, now I want to reread SC to what else I can pick up

Anhun, that idea about LotGK feeding on Depression and inner darkness is spot on. I am sure it is no coincidence that the perkiest Marsh-Wiggle, Puddleglum, is the Narnian sent to challenge her, no more than it is the bravest Narnians (Ourius, the Beavers) who are sent to challenge Jadis the tyrant.

Lucy once asked Aslan if he is in their (our) world. Aslan replied Yes, but that "there I have another Name. You must learn to know Me by that Name. It is for this purpose that I brought you into Narnia," so that the Pevensies might know Aslan better, by the Name here, in their own home.

Therefore I would argue that the witches are different for the obvious reason that the children are different. The Pevensies met Aslan during World War II, a time when assorted tyrants controlling assorted armies attempted to inflict assorted forms of death upon us all. (Which, BTW, if the one in Germany had not been so reckless as to attack the one in the USSR, the Allies might not have won the war.)

The Pevensies therefore challenge a tyrant-sociopath in Narnia. I use the term in the Diane Duane sense of her description of the tyrant T'Rehu (The Romulan Way). Duane reports

"She was one of those people with that inexplicable quality that Terrans call 'charisma' and Rihannsu call 'nuhirrien' ['look-toward'] .... She simply had that quality of being followed. Some have used the word 'sociopath' to describe her, but the term loses some of its meaning in Rihannsu culture, where one is expected to reach out one's hand and take what one wants" [as T'Rehu assuredly did].

(Having said that, Jadis would wipe the floor with T'Rehu, who deteriorated into a financial failure after her military success.)

Jill Pole and Eustace Scrubb, however, meet Aslan in the post-war world in the care, if we can call it that, of practical, Gradgrindish, reductionist schools. The world having had enough of high passions, its horizons to the eyes of "Pole" and "Scrubb" were limited to only what they could see and test and reproduce according to a sort of scientific protocol. Indeed, this early stamp on their impressionable souls continues to leave its mark, as the characters still call each other Pole and Scrubb to the end of the series. Does Aslan call His beloved one "Pole"? Of course not. That's impersonal, and Aslan is an intensely personal Being.

Therefore Jill Pole and Eustace Scrubb, to learn to know Aslan by another Name in our world, were sent against a practical witch. With apologies to our atheist friends here -- LotGK is one of the militant ones, not one of the let's-talk-about-this ones -- LotGK struck me from the first as the angry atheist. She tries to hypnotize Puddleglum and the children to reject Sun, Aslan and Sky as just immature, buy-me-a-pony fantasies about mundane tangible things like cooking fires, kittycats, and cells. Then, when she fails to break her prisoners, she flies into a murderous rage and literally becomes a snake-in-the-grass. C.S. Lewis made constant digs at schools and schooling through his writings, and it makes sense that two children and a Marsh-Wiggle should face the challenges he faced and then actually win.

Summary: of course the villains are different people. The children they face are different people.

As regarding the argument that they could be the same people because they might be immortal, well, Morgoth, Sauron, and Saruman all started out immortal, and no one thinks they're the same people. We could have a long discussion about why each age got each villain -- Morgoth versus Feanor's pride, Sauron versus Celebrimbor's survivor's guilt, Saruman [lit., "smarty-pants"] versus "dummies" like trees and mostly illiterate horse-herders -- but that's a debate for another thread.

I spotted this on Wikipedia and thought it might be worth adding to the discussion for interest's sake:

Some readers believe that Jadis and the Lady of The Green Kirtle are the same person. Jadis, however, is slain by Aslan several hundred years earlier in The Lion, the Witch, and the Wardrobe, and Lewis never describes her being brought back to life.

The speculation is probably reinforced by the set of character sketches included in some later editions of the books. One sketch describes Jadis as "completely evil, even in The Silver Chair." Since it is the Lady of the Green Kirtle who appears in The Silver Chair, some conclude that this must refer to the Green Lady. The character sketches, however, are recent additions to the books; they were not written by Lewis, and, in this regard, are not supported by Lewis's text. Lewis scholar Peter Schakel even writes that the character sketch "states incorrectly that the Queen of Underland is an embodiment of Jadis".[1]

The BBC cast the same actress (Barbara Kellerman) for both roles in the TV adaptations, which may have added to the perception that they were the same person or at least connected. This choice was due at least in part to the limited budget of the TV productions;[citation needed] several other actors were also cast in multiple roles to save money (Kellerman was also cast as a hag in Prince Caspian).

The mechanics of how Jadis could return are never made clear, since she is killed at the end of The Lion, the Witch and the Wardrobe, her last chronological appearance in the books. In Prince Caspian, Nikabrik and his companions suggest that the White Witch could be resurrected — "who ever heard of a witch that really died?" In Lewis's text this plan is never put to the test, though the Walden Media film adaptation introduces a ritual that begins to pull Jadis back to life before the spell is broken.

Personally I think they're different people. I believe Aslan really did kill Jadis and Nikabrik's comments were meant more like the Narnian equivalent of use of a Ouija board or something like that. And I think if Lewis really meant them to be the same he would have said something.

I've been thinking about this discussion more as of late thanks to The Silver Chair moving along with pre-production, and this morning I was looking over the notes I took several years ago when I wrote down every bit of dialogue the WW and the LotGK ever spoke. I was kind of obsessed with settling the question in my mind back then, so comparing their speech patterns helped a lot.

As opposed to Jadis's 3700 or so words of dialogue, the LotGK only has about 800. Even in that small sampling, we see many phrases and words that Jadis never used: I pray you, I cry you mercy, fie upon you, thither, shalt, thou, thy, et cetera. There is a dulcet poetry and certain archaic quality in the LotGK's manner of speaking that Jadis never possessed, even when trying to tempt Digory with the apple or Edmund with the turkish delight.

What stood out to me this morning when I was going over my notes, however was the fact that four times the LotK calls Rilian "lord"—my lord, my lord Prince, your Lordship. Can you imagine Jadis ever calling anyone her lord? I genuinely cannot. This is a woman who chose to kill every living thing on her planet rather than yield her throne. She is pride itself! Saying something like that would be profoundly out of character for Jadis, and I can't imagine that she would have any interest in ruling through a puppet king, either.

If they are supposed to be the same person, I think Jadis must have had a personality transplant at some point.