We have at home the numbers 5 and 7. You know, one of those habits that you take as a child. All boys and girls ever pick their favorite number, a small part of the identity they're building, another piece. There's complicity between friends, because that's a number like that, I like the same number. Although we think it's personal, we have a social option fundamentally, because the society around us pushes us to own a number -- not two, or four. It is necessary for each to have his/her favorite number in order to be homologated among equals.

“Dad, what’s your favorite letter?” my 4-and-a-half-year-old innocently asked me. The question surprised me. At first I laughed thinking it was a rare occurrence of a young child. But then I realized the logic children use: if there are preached numbers, the letters can also be the subject of amulet.

I'm looking for my favorite letter. It's never too late to complete the puzzle.