Letter 79 — On the Rewards of Scientific Discovery (§6)

“It makes a great deal of difference whether you approach a subject that has been exhausted, or one where the ground has merely been broken; in the latter case, the topic grows day by day, and what is already discovered does not hinder new discoveries. Besides, he who writes last has the best of the bargain; he finds already at hand words which, when marshalled in a different way, show a new face. And he is not pilfering them, as if they belonged to someone else, when he uses them, for they are common property.”