ONE WEEK the Soviet Union seems to be tumbling into economic chaos, the next into ethnic disintegration, the third into incipient popular rebellion or civil war. There seems no bottom to the downward spiral, and a black despair touches many Soviets beholding it. Mikhail Gorbachev long ago lost his magician's image, and the overwhelming political issue has become not who will govern the country but whether it can be governed at all.

With all this, it is easy to forget there is still a responsible public life in the Soviet Union. It reveals itself in surges of effort to come to grips with the country's aching difficulties. With a typical convulsion, the legislature has just approved a program offered by Mr. Gorbachev and meant by him to take in hand what remains of the centrally planned economy, halt its free fall and reorganize it on free-market terms.

It is, thanks to glasnost, widely noted that the program is a compromise. The radical reformers' hope to match Poland's example of going "cold turkey" from plan to market has been abandoned. There is, rather, a jumble of goals: to privatize state-run enterprises, to rein in a galloping inflation but meanwhile to retain considerable authority in the ministries at the center and to dispense just enough authority to co-opt the republics but not enough to lose them.

These hesitations in the Gorbachev program are widely depicted as defects, harbingers of failure. While much advice on organizing a free-enterprise economy has moved in a direction from West to East, the tone of economic debate has moved in a direction from East to West: in Moscow the mood is stark and apocalyptic and it has rubbed off on much of the comment in Washington.

But it is not as though we had organized our own (vastly simpler) affairs so brilliantly -- least of all in recent days -- that we have earned license to advise on theirs. The transition the Soviets are attempting has no precedents, no models, no rules. Spotting its contradictions is easy. What Mr. Gorbachev must do is to resolve these contradictions within the new Soviet political context that is his bane and his finest achievement at the same time.

He must work, in particular, with a Boris Yeltsin who has used his status as an outsider to preempt the populist high ground. It still seems that no reform can begin to bite that does not draw in both of these two larger-than-life figures. It is in the political chemistry and not in abstract economic formulations that the world must look for signs of whether the Soviet future is going to work.