Letters 55.11

A friend should be retained in the spirit; such a friend can never be absent. He can see every day whomsoever he desires to see.

I would therefore have you share your studies with me, your meals, and your walks. We should be living within too narrow limits if anything were barred to our thoughts. I see you, my dear Lucilius, and at this very moment I hear you; I am with you to such an extent that I hesitate whether I should not begin to write you notes instead of letters. Farewell.

Seneca, Letters to Lucilius 55.11, translated by Richard Mott Gummere