Historians argue among themselves whether Thucydides is a moralizing philosopher or, in a common phrase, “the first scientific historian.” What is radical about him, and gives him his unerring clear-sightedness, is that he is both. He understands morals, not as a set of arbitrary rules imposed or wished upon reality, but part of the fabric of reality itself, in the same way that Greek philosophy had begun to understand physical laws as inseparable from reality. Thucydides came to the same insight that Ludwig Wittgenstein recorded centuries later when he wrote that ethics “must be a condition of the world like logic.”
In Thucydides’s morally coherent universe, moral action is also, inevitably, practical action, and immoral action is inevitably impractical, no matter how insistently short-sighted [?] strategists pretend that it isn’t. ...
Emphasis mine. You'll want to read the whole piece, especially the giant chomped-out quote from Thucydides himself (it's chillingly accurate), but I want to touch on that passage in particular because of what else it reminds me of.
One of the big things that drew me to Buddhism in general and Zen in particular was how it is intended to be a practical philosophy — something you do, not just something you think about. It took a while, and a few different people explaining it in their own ways, for that to really sink in with me, but once it did, pow.
Buddhism doesn't have moral codes per se. What it does have is a set of guidelines about what you can expect if you do or don't do certain things. If you don't kill people, don't lie to them, don't steal their stuff, don't misuse them sexually, and don't mess up your organism with drugs (and, it's also stated, inspire other people to do the same thing), you generally have less grief in your life. You also tend to have less grief in other peoples' lives, because you're not forcing them to clean up after you or dragging you down with them.
Sometimes you have to break these rules. If Jason Voorhees breaks into your house and tries to hack your head off, you're fully justified in trying to hack his head off. Nowhere does the Buddha command anyone to be a doormat. But the exceptions are generally going to be very self-evident. For the most part, if you stick with the guidelines, there's less drama and nonsense.
This is the key point being made in the quote above. The right thing is in big part the right thing because it's also highly practical — it makes everyone's lives less of a hassle in the long run. If I choose something that makes me happy (for all of five minutes) but makes everyone else around me unhappy, their unhappiness is eventually going to become my problem whether I like it or not, even if it's just in the form of me having to expend more and more of my own energy and resources in shoring up a defense against it.
If you sit quietly with yourself for long enough and let the b.s. fall away, these things stop becoming things you have to talk yourself into, and more things you can witness and realize for yourself. That to me is where Zen picks up where a lot of other things leave off. It's not about talking other people into something they can't be talked into; it's about equipping them with the tools they need to see for themselves why this is so. You may not convince everyone, but even just convincing a few people is helpful. If those few people can turn down the volume of the drama in their own lives, it helps.
My chief point, again, is that the right thing to do is almost always also the sensible thing to do. The wrong thing is almost always the overcomplicated and impractical thing in the long run, because it requires you to lie, and then lie about having lied, and then get other people to lie about your lies, and so on. The words of Barrows Dunham come back to mind: if you want to be a tyrant, you have to be the sort of man that, in the end, builds gas chambers and herds children into them. And all that for what, exactly? "The gains hardly seem worth the degeneracy," as he so memorably put it.
And when you get down to it, the right thing to do is not that complicated to figure out, so long as you are not obsessed with putting yourself front and center in all things. It fairly shouts at you, in fact, once you quiet yourself down long enough to hear it.
New York City
Other Lives Of The Mind