Letters 79.6

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.

Seneca, Letters to Lucilius 79.6, translated by Richard Mott Gummere