Ttyjukl

The Eye of the World, from Robert Jordan's Wheel of Time series, and the Well of Ascension, from Brandon Sanderson's Mistborn series, seem to be far too similar for coincidence. Here follows a lot of evidence, so if you're already convinced, skip to the bottom for the good bits:

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  a pool filled with mysterious fluid

  
  
  

  tEotW:

  
  
  

  
  

  a pool took up the entire cavern, except for the walkway around it, perhaps five paces wide. [...] Its surface was as smooth as glass and as clear as the Whispering Water. Rand felt as if his eyes could penetrate it forever, but he could not see any bottom to it. [...]

  
  
  

  The stone struck the glassy surface and slid into the pool without a splash, or so much as a ripple. As it sank, the rock began to swell, growing ever larger, larger and more attenuated, a blob the size of his head that Rand could almost see through, a faint blur as wide as his arm was long. Then it was gone. He thought his skin would creep right off his body.

  
  

  
  
  

  tWoA:

  
  
  

  
  

  Staring at the glittering waters. They were gathered in a small depression in the rock, and they looked thick - like metal. A silvery white, glowing liquid metal. The Well was only a few feet across, but its power loomed in her mind. [...]

  
  
  

  She stepped onto the pool. It resisted her touch, but her foot began to sink, slowly.

  
  

  
  


• 
  

  an immense reserve of power, to be used in great need

  
  
  

  tEotW:

  
  
  

  
  

  "The Power to mend the seal on the Dark One's prison, or to break it open completely. [...] No one living knows [...]either the how, nor more of the why than that it would be needed one day, and that that need would be the greatest and most desperate the world had faced to that time. Perhaps ever would face.

  
  

  
  
  

  tWoA: I can't find a relevant quote, but the power from the Well of Ascension is what the Lord Ruler used to reshape and shift the entire planet, and what Vin could have used to do the same if she'd understood what was really going on.

  
  


• 
  

  ... power which the main character takes, emptying the pool

  
  
  

  tEotW:

  
  
  

  
  

  Light filled him, and heat that should have burned yet only warmed as if it took the chill of the grave from his bones. [...] Rand pulsed with the beating in the cord, like the heartbeat of the world. It filled his being. Light filled his mind, till only a corner was left for what was himself. [...] Warmth built in Rand, the warmth of the sun, the radiance of the sun, bursting, the awful radiance of light, of the Light. [...]

  
  
  

  "The Eye is gone, but there's something in the middle of the pool, a crystal column, and steps to reach it."

  
  

  
  
  

  tWoA:

  
  
  

  
  

  she started to burn. She recognised the sensation: it was exactly like the feeling of burning metals in her stomach, except it came from her entire body. Her skin flared, her muscles flamed, and her very bones seemed on fire. [...] She was glowing. She felt the power within, as if it were trying to burst back out. It was like the strength she gained by burning pewter, but amazingly more potent. It was a force of incredible capacity. [...]

  
  
  

  She screamed, her glow fading, then fell into the now empty pool, head knocking against the rocks.

  
  

  
  


• 
  

  up in the far northern reaches of the world

  
  
  

  tEotW is far out in the extreme northeast of the continent, beyond the Blight.

  
  
  

  tWoA is actually under Luthadel, but was rumoured to be (and in fact was, in earlier drafts of the book) in the northernmost Dominance, that of Terris.

  
  


• 
  

  with a book named after it.

  
  
  

  tEotW: all quotes above come from book 1, The Eye of the World, chapters 50-51.

  
  
  

  tWoA: all quotes above come from book 2, The Well of Ascension, chapter 58.

  
  

Was the Well of Ascension definitely based on the Eye of the World?

Are there any quotes from Sanderson himself to confirm or deny this?

I think you've simply pointed out that most Fantasy works are to a greater or lesser extent derivative. Either from other Fantasy novels, most often Tolkien, or from existing mythologies from around the world. The WoT series itself is based to an enormous extent on both the Lord of the Rings and the Arthurian legend.

To focus on the specific points you made:

1. 
   

   A pool filled with mysterious fluid

   
   
   

   This is a very common trope in Fantasy literature which, to my mind, harks back to the Arthurian legend of the lake. While that lake, as far as I know, is always described as made of water, it is also often described as eerie and a place of power. In some versions of the story, a hand appears out of the lake to offer Excalibur to Arthur:

   
   
   

   

   
   
   

   While in others, Arthur threw the sword into the lake. In both cases, however, a hand appears to either grab or offer the sword. I think that qualifies as a mysterious body of water.

   
   
   

   You could also make a valid argument for its representing the fountain of youth or even the waters of the Styx in which, in some tellings of the story, Achilles was dipped and became invulnerable.

   
   
   

   Whatever the choice, there are many, many references to mysterious lakes around. Finally, note that there is no explicit suggestion that the liquid in tEotW's pool is not water, while it is most certainly not water in the Mistborn books.

   
   


2. 
   

   An immense reserve of power, to be used in great need

   
   
   

   Another classic trope. In Tolkien this is the One Ring: an artifact of near limitless power which everyone is after and which has become a thing of legend. In any case, Fantasy literature is littered with artifacts of enormous power that some character or other manages to retrieve and use. You could say that this too is related to Arthur and the quest for the Holy Grail.

   
   
   

   In any case, there are more stories of mystical items imbued with terrible power out there than you can shake a magic sword at.

   
   


3. 
   

   Power which the main character takes, emptying the pool

   
   
   

   I can't, off the top of my head, remember any other examples where a pool, specifically, is emptied and power given so sure, maybe this one did come from WoT. Still, the general idea of a body of liquid hiding something which appears once it is drained is as old as the sea.

   
   


4. 
   

   Up in the far northern reaches of the world

   
   
   

   This is not even a Fantasy trope. Anything legendary is always off somewhere far away. Very often in the north which is frozen and hard to get to. Santa Claus, for example. Or, for something more Fantasy, in George R. R. Martin's A Song of Ice and Fire series, there is a mysterious land in the north (north of the wall) where strange creatures dwell and magic is still strong.

   
   


5. 
   

   with a book named after it.

   
   
   

   Well, if we take this immense reserve of power as the object of the title and not, specifically, that it was a lake, The Fellowship of the Ring would also qualify. In any case, naming a book after an item which the main characters spend most of the book searching for or protecting is hardy uncommon. From The Golden Compass (which also had a thing about the far north) through The Deathly Hallows to The Blinding Knife, authors have named their books after significant plot items.

   
   

Don't get me wrong, almost by definition, Fantasy novels will be derivative. Such is the nature of the genre. And that's not necessarily a bad thing. I don't mind a good retelling of a classic story and I enjoy new versions of the classic tropes. However, going from "these books share some common elements" to "one is a based on the other" is a pretty huge leap. None of the examples you cite make me think that this is the case here.

So no, I don't see any reason to believe that the Mistborn series is in any way based on the Wheel of Time. For one thing, unlike WoT, which is basically a retelling of the classic Fantasy trope: young boy is discovered by a powerful Wizard and is led to fulfill his destiny, and is quite explicitly based on the Arthurian legend (Berelain sur Paendrag Paeron, Artur Hawkwing, Luthair Paendrag Mondwin, Morgaine, to name a few), the Mistborn series are at least presenting a very original and indeed unique system of magic.

In conclusion, I think you have simply noticed some very, very common tropes that you will find in many books. I assume you simply first came across them in the WoT series which, given your user name, you are quite fond of and that's why you think other books might be based on them. If you go far enough into the abstract, you can make a good case that both WoT and the Mistborn series are based on an even older trope: the coming of the Messiah. In other words:

The Wheel of Time turns and Ages come and go, leaving memories that become legend. Legend fades to myth, and even myth is long forgotten when the Age that gave it birth returns again. What was, what will be, and what is, will be written again and again, by different authors, with different words and yet will always be the same.

I think it's one of the cases when asking such question may make sense - it's probably something more then repetitiveness of tropes. Sanderson was asked about that and he also does seem to think so:

Questioner

So I was reading the Wheel of Time and in the first one when they get to the saidin and saidar, the pools—they're very similar to Shardpools.

Brandon Sanderson

Yes, and that is something that he kind of dropped. The Eye of the World is just like pure saidin, and I would be surprised if that weren't an unconscious influence on me. I didn't think of it when I was coming up with these but that's definitely way back in my brain when I was creating these.

As one might suspect it wasn't deliberate influence. He also mentioned:

It's very heard to separate out what in my series is WoT influenced--since all of it is influenced deeply by reading the WoT when younger. So I'd say it most certainly was.

Actual origin of Shardpools goes back to Elantris, where Sanderson used "Well of Power" trope, but it wasn't that similar to the Eye of the World. He described development of this:

When I put the first Shardpool in, I had-- I'm just like "Here's a well of power. I don't know what this does." I was discovery-writing the book. By the time I sold Mistborn and Elantris, I sold those two in a deal in 2003, that's when I'm like, "All right, now I'm gonna do this for real." I've had all this trial run-- I'd written thirteen novels at this point, and I'd sold #6 and #14, Mistborn not being written yet... So, I sat down with Elantris, and I built out the cosmere, and I built out these things, like "Why do I have this pool of power? What am I gonna do with the pool of power in the next book? I want this to be a theme." And I started building out the cosmere from there. So, part of it was organic, part of it was by design.

So, while it's quite possibly that this trope occurs in his works because it was also used in the Wheel of Time, and fit in Elantris, there were various things that could be done with it and actually getting raw power from the well wasn't the first of them at all.