IF ISRAELI FOREIGN MINISTER Moshe Dayan accomplished nothing else in Washington, he put at least a temporary gloss of flexibility on an Israeli policy that had seemed increasingly rigid and negative since Prime Minister Menachem Begin's visit here last July. Perhaps this, rather than real progress toward a settlement, was his purpose. Many Israelis believe that, in the absence of Arab readiness (as they see it) for peace, Israel should concentrate on looking reasonable enough to the United States to ensure continued American favor. In that sense, Mr. Dayan, with his war hero's aura and his capacity to project the possibility of the unexpected, is the perfect foil for the heavy, relentlessly pious Begin. The Arabs, always ready to suspect the Israelis of tactical diversion, have a special grim regard for the architect of their humiliation in 1967.

But another view is also plausible. It is that the Israelis have taken to heart some of the stern criticism directed against certain of their policies by the Carter administration and by broad elements of the American public, and that they realize they must help find ways to advance American diplomacy rather than block it. The Israelis now seem to understand just how important it is to the policy and the prestige of the Carter administration to reconvene the Geneva peace conference soon. Mr. Dayan may have offered a hint of movement on the roadblock of Palestinian representation, while soliciting Arab movement.

This maneuvering leaves open whether a Geneva conference would be a mere "photo opportunity" or whether, as serious people must hope, it could be a prelude to and catalyst for serious bilateral bargaining, perhaps with the United States again in a shuttle role. But stalemate carries its own dangers; these lie in the frustrations it breeds among Arabs. The Carter administraion has made a solemn commitment to search for a Middle East settlement, and it cannot afford to slacken the pace.

American officials argue that the important thing is to get away from the formal exposition of "positions" and, instead, to get a process of exchange going. They are right. It is useful and necessary to have an idea of where you want to go; the administration earlier so indicated by laying out its ideas on territorial withdrawal, a Palestinian homeland and meaningful Arab-Israeli ties. But it is no less useful and necessary to be open to different ways of reaching these goals. This is the light in which Mr. Dayan's idea of West Bank autonomy ought to be regarded. It is an appalling idea if one thinks of it as the final outcome, but it possibly has some value as a transitional arrangement. We are eager to see what Foreign Minister Ismail Fahmy, who begins his meetings in Washington today.