And again, I think, crucially, it has to do with refining our ethical intelligence. It has to do with refining our capacity to see where our impulses are coming from, to what extent those impulses are just driven by conditioning and habit and fear, and to what extent we can somehow open up a nonreactive space within us from which we can respond to the world — respond to our own needs, too — but in a way that’s not driven by familiar habit patterns, which are often rooted in attachment and fear and other things. So solitude, the practice of solitude, is the practice of creating an inward autonomy within ourselves, an inward freedom from the power of these overwhelming thoughts and emotions.
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Nirvana is not some Buddhist heaven somewhere, someplace you go to after you die or some deep mystical experience you might, if you’re lucky, land in, one day. But nirvana as the Buddha defined it is simply the absence of greed, absence of dislike, and absence of egoism. In other words, it is described as a kind of — it’s a solitude in which you’re not being crowded out by your attachments and your fears and your egoistic confusions. That’s what you’re solitary from.

You see, in Tibetan and some of these Asian languages, you can use solitude as a verb. You could say, “I’m solitary of anger,” which means, “I’m empty of anger.” If you look it up in a Tibetan dictionary, it gives as a synonym, emptiness.

... And in that sense, it’s a constant, ongoing ethical inquiry and refinement of a sensibility that will always be with us, because perfection in human life, I think, is a pipe dream; [laughs] that life is constantly throwing us situations that we could not conceivably have foreseen — our body gets sick, breaks down, all of these things. And at each moment in our existence, we’re constantly aware that we are faced with choices. It’s always a challenge — our lives are always a work in progress. We are unfinished projects, and we’ll still be an unfinished project when we die. But that is what gives this whole way of living its urgency, its dynamism, and also, I think, its deep joy, its deep sense of flourishing as a person.