He didn't bother addressing the question of what a quantum brainwave is, mostly because he didn't really know himself. The idea of her being 'just' a magic user struck him as... odd. Sure, she had a point with her analogy, after all, one didn't need to know how a mobile suit worked in order to pilot it, but by the same token...

"But don't you think you should know how your magic works, so you can use it to its full potential?"