Supergirl, Season 2

Lena:
[getting emotional] You know, I... just thought if I could make this work, I would prove to the world and... to my mother that I was as good as the Golden Boy. I think most of all, I just wanted to prove it to myself.

Rhea:
You don't have to prove anything. You're smarter than Lex. [Lena demurs] No, I'm not saying that to make you feel better. I'm saying it as a scientist. As someone who knows. But you need to stop trying to think like your brother. From what you've told me about Lex, he's a man who's concerned with power. And that's how you've been trying to fix this. Give it more power, you think it will work.

Lena:
Yeah, and it just keeps blowing.

Rhea:
But you're not a person who's consumed with power, are you? So if you weren't trying to do what Lex would do,... what would you do?

Lena:
[considering] I'd... try to find a way to increase the anion input without overloading the energy output, all while maintaining the element's synthesis rate as a constant.

Rhea:
Not power. Balance.