Why can't the Aes Sedai fix the seals?

Question

If the Aes Sedai can sense the seal against evil breaking, why don't they all get together and close it… problem solved?

Answer 1

If you're referring to the Seal on the Dark One's prison:

They don't know how.

The Seal was done by Lews Therin and the Hundred Companions (113, actually), and it killed 45 of them. It's important to note that these Aes Sedai were all male channelers that were experienced and trained in the Age of Legends.

"Modern" Aes Sedai are typically weaker than channelers from the AoL. They've also lost a lot of skills and knowledge. For instance, the Seal used 7 cuendillar disks as anchors. It's only towards the very end of the series that Egwene al'Vere rediscovers how to make cuendillar. Even then, few Aes Sedai are even capable of producing it.

The Seal itself required more weaving than just making cuendillar. The details of which are surely more complicated, and requiring greater ability with the One Power, than making cuendillar.

It would likely require a greater number of powerful channelers than existed.

Nynaeve and Egwene are the most powerful Aes Sedai respectively. It's not until later that other, non-Forsaken, more powerful female channelers are discovered (Alivia and Sharina, respectively).

According to popular understanding, there's less than 1000 Aes Sedai in the world during the events of the Wheel of Time series (this is stated in Lord of Chaos, Ch. 37). Many of them are not notably powerful (see this fan-made, but likely accurate, ranking of Aes Sedai). Since channeler power is distributed on a bell curve (author quote available in previous link), the reason Third Age Aes Sedai are most likely weaker than the AoL males is that there's a smaller pool of channelers to choose from. In the AoL, the greater raw number of channelers meant there were a greater number of powerful channelers.

There could be severe consequences

It's heavily hinted at throughout the series than in order to re-seal completely fix the Dark One's prison, the seals must first all be broken. So, another reason is that the Aes Sedai would not be willing to risk Tarmon Gai'dan and unleashing the Dark One. Aes Sedai (being wise, or at least believing themselves so) would realize that tampering with something they had no idea how to handle could have potentially devastating consequences.

I would note, that Egwene, with her visions of Rand breaking the seals, would most likely be the only Aes Sedai to know about breaking the seals first. She had two possible related dreams, and spoke about them with Moirraine:

"His feet crunching," Egwene said, staring Moiraine in the eyes. "As he strode forward, Rand's feet stepped on the shards of the Dark One's prison. I saw him, in another dream, hacking away at it to open it. But I never actually saw him opening it, Moiraine."

"The shards were there, Mother," Moiraine said. "The seals had been broken."

In-universe, it was only Min and Rand that were directly familiar with this concept (thanks to Herid Fel), and whomever they confided in.

Answer 2

Simply put, the Aes Sedai do not repair or replace the seals because:

1. They know to do so would also drive all female channelers insane.

Robert Jordan

The result of this was that Lews Therin carried out his plan with only male Aes Sedai, so there were only male Aes Sedai channeling there, which was a lucky thing, because if there’d been women as well, then both saidin and saidar would have been tainted. And his plan worked, except for that one side effect of the backblast which tainted saidin and caused him and the men there with him to go mad there and then, and other male Aes Sedai to go mad slowly as they touched the Source and began to absorb bits of the taint. But that’s why saidar was not tainted, because there were only men there channeling during this act of sealing up the Dark One’s prison

This is one point that is clear: the Aes Sedai do know that the reason saidin is tainted is because of the backlash due to sealing the Dark One.

2. The seals are an imperfect fix, they only last for a few thousand years or so, and to buy this time they would corrupt saidar.

3. Originally it only required a circle of 13 men/women combined.

   "The Strike at Shayol Ghul"- A summary

Lews Therin proposed that the Dark One be resealed in his prison by plugging the Bore. The plug would be inserted by thirteen linked male and female channelers and would be held in place by the seven seals, which were focus points of the weaving. 20,000 soldiers would accompany them to Shayol Ghul, where the Bore could most be sensed.

But

Opponents argued that the Seals required precise positioning, and that any slight error would tear the Bore open wider.

And so

Robert Jordan - And in the end, what resulted was the so-called “Fatal Covenant” [It was actually the “Fateful Concord”], which had the female Aes Sedai swearing not to go along with Lews Therin’s plan

Finally

Lews Therin decided that something had to be done right away, so he covertly organized 113 male channelers who supported his plan (they were later called the Hundred Companions, a slight miscount) and over 10,000 soldiers who were also loyal to him. The force stormed Shayol Ghul, when all thirteen Forsaken were there, and put the Seals into place. At the moment of the resealing, the Dark One drove all of the surviving Hundred Companions (about 68, at that point) instantly insane. The Dark One also tainted saidin, although this wasn't discovered until after hundreds of other male channelers had been driven mad from it.

From this we can see it did not require 113 channelers to place the seal, it would only have required 13 male/female channelers, so Power was not something needed here it was finesse, as pointed out in the counter argument of the female Aes Sedai, aka precise placement.

So to conclude this point the Aes Sedai had the power required to place the seals, but not the...

4. Knowhow.

Egwene has rediscovered how to create cuendillar, but it is unclear if the seals are more then just cuendillar or not.

So it's speculative at best if they could create new seals.

Finally

They would have zero idea of how to actually place the seals:

Opponents argued that the Seals required precise positioning, and that any slight error would tear the Bore open wider.

Aes Sedai in the Age of Legends, who understood how and why the Bore was created, and understood essentially the physics of the Bore, could not agree on proper placement. By the time of Egwene, her Aes Sedai have almost none of this knowledge and would be essentially placing the seals on the Bore blindly.

Which leaves us with

5. Aes Sedai know the above points, and so are actively looking for new ways to seal the bore, aka Callandor, which all of their prophecies point towards in relation to the Dragon Reborn. The original plans were to control the Dragon Reborn and give him Callandor right before he faces the Dark One. Both Siuan, Elaida, and Egwene have similar thoughts on this, and all resent Rand for essentially being free to do as he wishes. But that is the plan the Aes Sedai have made to stop the Dark One, hanging their bets on the Dragon Reborn, in some form or manner.

Answer 3

Actually it was Egwene who rediscovered cuendillar. Moghedien understood the principle but didn't know the weave. And Rand himself told Egwene that he thought that the reason the original seal was flawed was because he needed saidin as well as saidar...notice he used both to cleanse the taint, and in the end when he fixed the Bore, he was linked with Nyneave and Moiraine, so apparently a full circle wasn't needed. Just 2 women 1 man, both women using angreals.

Answer 4

Primarily because the knowledge and power needed to do so has long been lost. Men filled the hole the first time (in theory the women could do the same) and men are hunted down like animals and dealt with permanently one way or another. As well as a host of other reasons. including the location of the breach.

Answer 5

It could be that: Aes Sedai could not make cuendillar until it was rediscovered by Egwene, Nynaeve and Elayne in Salidar. They learnt a lot from Moghedien when they had her prisoner as Marigan in TFoH.

Answer 6

Every statement above is correct excepting some of them.

1st: The seals were formed with Saidin which means they can only be effected by Saidin. If they had been formed with both halves of the power the sealing would have worked.

2nd: The reason Saidin is tainted now is because the female channelers refused to help fix what they had broken in the first place.

3rd: The male half of the One Power has been tainted for so long and practically every male channeler the tower has gotten their hands on has either committed suicide, used as an example(the White Tower's Red Ajah is infamous for this), or just outright slaughtered by the people around them after they were stilled(yes stilled not gentled. Calling it one thing when used on men and claiming its the right thing and then admitting its a terrible punishment when used on women is counterintuitive.) and basically tying them to a stake to burn.

Lastly you can tell the female views throughout the series on men having power of any kind, and its condescending as hell. If the Aes Sedai from the Age of Legends saw this behaviour they would all be punished for their presumption as the role of Aes Sedai was what their name LITERALLY meant. Servants of All NOT Everyone else serves you.