When people mean to be good to you, you don't mind very much when they're not quite—always. — L. M. Montgomery. Canadian novelist (1874–1942) Love
Anyone who has gumption knows what it is, and anyone who hasn't can never know what it is. So there is no need of defining it.
Proverbs are all very fine when there's nothing to worry you, but when you're in real trouble, they're not a bit of help.
It's not vanity to know your own good points. It would just be stupidity if you didn't; It's only vanity when you get puffed up about them.