Letters 113.24

One might say: “The virtues are not many living things, and yet they are living things. For just as an individual may be both poet and orator in one, even so these virtues are living things, but they are not many. The soul is the same; it can be at the same time just and prudent and brave, maintaining itself in a certain attitude towards each virtue.”

Seneca, Letters to Lucilius 113.24, translated by Richard Mott Gummere