WHEN I LONG FOR ESCAPE, I dream of the prairie. The last time I was out west, visiting my childhood home in Pierre, South Dakota, I drove up to one of the river hills on the edge of town. Why is the sun so much bigger out on those plains than it is back east? Sitting on the warm hood of the car to watch the huge orange sunset beyond the Missouri, I thought: Here is where I ought to be, here is where I should stay.

Back east, out west, up north, down south: Our geographical prepositions have come adrift. Some memory of their grandparents' arrival in the Dakotas, some last lingering sense of the westward course of history since Columbus, made my parents insist we say "back east" and "out west." Back was civilization, the old country, the origin. Out was the frontier, the undiscovered country, the goal.

In her early books about a child's life on the frontier, Laura Ingalls Wilder tells of her family's wanderings from a log cabin in the big woods of Wisconsin, to a little house on the prairie in southern Kansas, and on to a sod dugout on the banks of Minnesota's Plum Creek. Her later volumes, however, chronicle her pioneer girlhood once her parents had settled down permanently, in a farmhouse near De Smet, South Dakota. And when an old Kansas neighbor visits on his way out to the new territory opening up in Montana, the teenaged Laura cries that her family should be

"'I know, little Half-Pint,' said Pa, and his voice was very kind. 'You and I want to fly like the birds.'"

But for me, east is where I flew away to, and west is back toward home. When I think about abandoning the life I have these days, I imagine living on one of those dry Dakota buttes overlooking the river, alone with my family, miles from the nearest neighbor--a final refuge from the noise and rush, a perpetual anti-Washington, anti-New York, anti-East, forever set apart and free.

Then I shake myself awake and remember that I'd probably starve to death attempting it. Perhaps my dreams of the prairie are merely the standard-issue reveries in which settled people imagine they might somehow throw off their responsibilities and make a change. Perhaps they're merely daydreams of difference: the perpetual illusion that life might be lived down some entirely other path, the always-shimmering mirage that promises we can find what our spirits are missing simply by relocating our tired bodies.

But there is also a current in the mind that seems, inevitably, to pull fantasies about the future down into the dangerous eddies of the past. I know that what we might call "second innocence"--our grown-up goodness, our adult perfection, if we could ever reach it--will have to be something different from the first innocence we knew as children. What we lost when we were young is not what we should seek when we are old. I know all that--and yet, the logic of human imagination always joins what might be with what has already been: every possible future somehow dependent on the past. Anyone can cure a patient's neurosis, an old psychoanalysts' joke runs. All you have to do is travel back in time and change the way his parents and grandparents were treated as children.