"To define is to limit"

From Oscar Wilde's Picture of Dorian Grey.

My second favorite one probably has to be

When I was young, I was told: 'You'll see, when you're fifty.' I am fifty and I haven't seen a thing.

From Erik Satie, one of my favorite composers.

EDIT: Whoops, I forgot to explain why it means something to me:

For the first quote, I always feel as though I'm limited by something. Whether it's my looks, or my gender, or my upbringing, education, interests, etc. etc. etc... I can't help but feel that none of those things can explain who I am, to be somewhat narcissitic. In the end, I try my best to avoid being labeled and "limited". I want to be the kind of person that you never know knows something you never thought I'd know. But that too, is a limit. In the end, I don't know what I want to be, but being limited is one thing I strive (though not steadfastly, for that too is limiting) against.

For the second quote, I often feel as though this life is all one huge joke. All I know is that the older I get the more I realize that no one truly knows what's going on and yet we pretend we do, or at least don't acknowledge that we're just as in the dark about everything as our children and make great efforts to appear to know more than we really let on. I also haven't seen a thing, at least not yet.