The four pillars of the national honor society
The four pillars of the national honor society are character,scholarship,leadership and service.
Because this is an essay for National Honor Society, you probably want to reveal a little bit about yourself within it, rather than writing a dry and objective essay. (I assume this essay is part of your application.)
The “dominant” pilar to me would suggest the one I most easily excelled in. Then I would talk about why that pilar was my strength, and how the others were either byproducts of such a strength, or characteristics necessary to have this strength.
So I would probably choose leadership. I happen to be a pretty natural leader and always have been. I would write one paragraph about how my character affected my leadership ability, one paragraph about how my grades were affected by my leadership, and vice versa, and finally, a paragraph about how service is a natural by-product of being a good leader.
Do you see where you have a lot of room to make this essay personal, and that there isn’t really one correct way to write it?