Dean Sluyter once had a cute formulation I've made use of myself. Instead of saying "Today is the first day of the rest of your life," he suggested substituting like this: "Now is the only moment of the rest of your life."
It's an extension of an idea you ought to know from me pretty well by now: the present moment is all we really have, and the only moment in which we can actually do anything. But it doesn't mean the present moment is the only thing that exists, or that plans are foolish things.
I had a tough time reconciling these two elements the first time I came into contact with this idea in anything like its modern (for me, that is) incarnation. If the present moment is everything and the only thing, then long-term planning — especially on a social scale, where it matters most — is also bunk, isn't it? But I knew all too well that couldn't be true; you needed five- and ten- and fifty-year programs in a world where seven billion plus people all jostled for space.
From what I've worked out, there's two ways these two ideas — now-is-forever, and future-plans — can and do coexist.
The first is that they address different domains of human spirit. The way Theodore Roszak put it once was that there's Out-There and In-Here. Out-There is the world where E=mc² and debts must be paid. In-Here is where 2+2=Fish. The two realms need different philosophies of action. Now-is-forever is about In-Here, and future-plans are about Out-There. Both require a different mindset — maybe "spirit-set"? — to be workable.
The second is that in the light of this first idea, the two ideas don't really contradict at all, something Sluyter himself pointed out. You can make plans for the future, but you only ever do so in the present moment, and so all plans have a tentative nature. Everything is provisional, although some things can be shown to be less provisional than others. (Karl Popper's ideas come to mind here, too.)
Another thing I've come to realize, as a product of all this, is how both are vitally important for different reasons. The rules we've put into place to make our world don't really work well for us on the inside. It's hard for us to be scientists about ourselves from the inside but we have to be — and my thought is that we have to go about it a different way from being a scientist about everything that's not us. I know that the latter worldview encompasses us whether we like it or not, because we're ourselves part of the world we're studying, but I think you get the point. We need a different attitude for ourselves, if only because, as Walker Percy put it, of all the phenomena out there in the universe, you are always going to be the strangest.
New York City
Other Lives Of The Mind