Letters 65.4

The Stoics believe in one cause only,—the maker; but Aristotle thinks that the word “cause” can be used in three ways: “The first cause,” he says, “is the actual matter, without which nothing can be created. The second is the workman. The third is the form, which is impressed upon every work,—a statue, for example.” This last is what Aristotle calls the idos. “There is, too,” says he, “a fourth,—the purpose of the work as a whole.”

Seneca, Letters to Lucilius 65.4, translated by Richard Mott Gummere