Board Thread:General Discussion/@comment-26580042-20160826010854/@comment-24674051-20160829170029

I might agree, except that I think that people can learn magic, IF they want to learn and are willing to pay the price. With Rumple (and all Dark Ones) and Merlin, Their magic abilities were granted and fully powered by the HG, and because of this they don't have the necessary training on their own (kinda like having a crutch, you don't build up your own muscles). Emma, Zelena, Ingrid, and Elsa were born with magic that was able to manifest itself without training (though later training was useful in order to control their magic). But these are the exceptions.

But Cora and Regina both had to be taught how to do magic, and I don't think they learned just because they had a "dormant" or "latent" ability. I would wager that they were able to learn only because they had a teacher that helped them. (and the same might be said of the Apprentice as well). And I think Anastasia was also able to learn only because she was taught by Cora. In fact, Jafar was also taught by Amara (Unfortunately, there is not enough story on Amara to know how she came to have her magic, though I do think that the Water from the Well of Souls factored into that). I think that a big reason there aren't more magicians is that magic is not easy (we saw some of Regina's struggles over the years), and there is a huge cost to casting magic.

In fact, going back to Season 2 (I think it was "We Are Both") Regina tells Henry that she could teach him how to use Magic. Now, 4 seasons later, I would say that she is capable of teaching him, but would probably try to convince him not to learn, but that's the change in her, not the change in Magic. (Besides, Henry has his own source of magic now).