Seneca, in his letters to Lucilius, urges him to choose a role model to provide a standard to live by. This is of course idea that is not unique to Stoicism by any means but Seneca succinctly puts why it is a necessary step in our pursuit of the good life. The person of our choosing can provide us with principles that can help us navigate even the most difficult and treacherous circumstances as well as standards against which we can judge our behavior on a day-to-day basis. As Seneca wrote,

“So choose yourself a Cato–or, if Cato seems too severe for you, a Laelius, a man whose character is not quite so strict. Choose someone whose way of life as well as words, and whose very face as mirroring the character that lies behind it, have won your approval. Be always pointing him out to yourself either as your guardian or as your model. There is a need, in my view, for someone as a standard against which our characters can measure themselves. Without a ruler to do it against you won’t make crooked straight.”