That Seneca the man did not always behave according to his own philosophy can be rejected as hypocrisy ("a steersman who is seasick in a storm"), but it would be a loss to disregard his letters to young Lucilius on those grounds. The selection of his letters translated by Robin Campbell - reportedly while he was serving in Africa with the Gordon Highlanders! - is rich with humane philosophy. This is not philosophy of the intellect but philosophy as guidance for character. In the first century A.D. Seneca lamented the specialization of philosophy into an intellectual discipline rather than an examination of how to live. I conversed and occasionally argued with these letters throughout the book, just as it should be.
(Although I have recently returned to Latin, which I studied in high school, I am not diving into the classics in Latin unless I have a good side-by-side translation.)
There are tempting parallels between daily Stoic philosophy and daily Zen philosophy, in that both propose that our suffering at the challenges of life are caused by our view of those challenges as much as the challenges themselves. Both acknowledge what Buddhism calls anicca - transience, impermanence - and stress an open-handed acceptance of phenomena as they appear. (Zen Master Dae Kwang, who taught for many years at Providence Zen Center, burst the balloon on calling this "detachment" because it humors the illusion that we can be attached to anything!) To be open-handed, however, can also lead to confusion and suffering unless there is a sustained practice of paying attention to our direction. As Zen Master Seung Sahn put it, "I always go with the flow - but I watch where the flow is going."
There is a crucial distinction, however, in what Stoicism (with Seneca for a spokesman) and Zen teach us about how to "hold" our minds, if you will.
Seung Sahn practically trademarked the phrase "don't know" to describe a lively clarity, an unhindered readiness to act, letting opinions and discursive thoughts come and go, without becoming identified with them in an egotistical way. "Don't know" actually goes "deeper" than this. Even the idea of ego ("I") can be let go. "Don't know" is a metaphor for consciousness before it gets organized into nominative thoughts, "before thinking." Click here for a brief excerpt from a talk by Zen Master Bon Soeng of the Empty Gate Zen Center about "don't know mind."
At conservatory, my acting teachers would warn me about the "stupor" of meditation. I challenged them to spend one week waking up with me to do prostrations and sit before breakfast. They did not take me up on it.
A normal human tendency is to identify with our thoughts ("I like this, I hate that") which leads us to defend our opinions and tastes as if they were our skin, and this makes non-contentious conversation with other people, therapeutic investigation, or casual reflection very difficult - even painful. A relaxed or "detached" attitude about our own thoughts helps with these things, especially those matters that challenge us to forgive ourselves and other people. ("Put it all down," as the Korean master said.) In fact, this is why daily meditation is prescribed - and why I have done some sitting (in very simple, non-guided, zen meditation) almost every day for 22 years. This actually requires repeated physical practice.
This is not a Stoic idea at all. Although Seneca, intriguingly, refers to some youthful experimentation with esoteric cults, and there were some encounters between Buddhism and the Roman world around Seneca's lifetime, I have not seen any evidence of an exposure to Buddhism and in any case this was "pre-Zen."
If "don't know" is the idea of holding our conscious mind loosely if at all, Seneca advises thinking everything through so nothing can take us by surprise:
What is quite unlooked for is more crushing in its effect, and unexpectedness adds to the weight of a disaster. The fact that it was unforeseen has never failed to intensify a person's grief. This is a reason for ensuring that nothing ever takes us by surprise. We should project our thoughts ahead of us at every turn and have in mind every possible eventuality instead of only the usual course of events. [From Letter XCI]
In practice, this is really a difference in metaphor more than practice. What is mind? Is it really something you can "hold" or "let go of" or "use?" These are all metaphors for how we direct our attention with respect to our thoughts and observations. Zen is radical in the sense that it questions the substance of self; the Stoics took no interest in this project. For the latter, the important matter was to transform a selfish "I" into an altruistic "I," but not to debunk the illusion of "I" itself.
It will be interesting to read Marcus Aurelius again, as his writings indicate more attention to habits of perception, not just the content of our thoughts, and a daily practice perhaps akin to samatha. For Seneca this seems to have been primarily a matter of receiving and implementing good teaching. The notion in Zen is that if we clear unhelpful habits of thinking away, and refer to the Buddhist precepts for guidance, a spontaneously humane nature ("true self") expresses itself. It may or may not conform to changeable and conditioned ideas about good and bad,but it is authentic and essentially humane.