I might not be modest but I am humble. I am not arrogant but vanity spills all over me.
P.S. After writing the above confession, I discovered that Jean Paul Sartre has a saying: I will not be modest. Humble, as much as you like, but not modest. Modesty is the virtue of the lukewarm. This reminds me: if you discover something that was already discovered but which you had no idea existed or how it came to be, or if you say something already said which you have never heard of, and although you will not be credited for it and although you will still be bound by copyright laws, that does not mean that you cannot credit yourself with such a discovery. You reinvented the wheel, maybe, you were not the first, certainly, but it is still your invention.