But suppose one doesn't quite know which one wants to put first. Suppose," said Harriet, falling back on words which were not her own, "suppose one is cursed with both a heart and a brain?"

"You can usually tell," said Miss de Vine, "by seeing what kind of mistakes you make. I'm quite sure that one never makes fundamental mistakes about the thing one really wants to do. Fundamental mistakes arise out of lack of genuine interest. In my opinion, that is.

Author: Dorothy L. Sayers