WITH pluralism a politically ``in'' word among communists in most East-bloc capitals, it is timely perhaps to assess how far it might go. For example, might it in time lead to a revival of socialist and other basically democratic East European parties swallowed up by the communists in their final seizure of power in 1947 and '48?
From Poland to Bulgaria, Socialist and Democrat, Peasant and Smallholder parties of long tradition were absorbed after years of pressure from communist parties which, though minorities in such postwar elections, as were held, always knew the Soviets backed them.
Some of these former parties were allowed to maintain a paper existence, preserving their old names. In Poland, they could even ``contest'' elections and hold seats allotted to conformist fellow-travellers with the ruling Communist Party, which had a guaranteed majority in parliament.
Recently, some old Polish socialists met in a Warsaw apartment to refound their party. At that time, Gen. Wojciech Jaruzelski was telling foreign journalists of his wish to establish a pluralism ensuring ``maximum participation'' in public affairs. At the same time, Polish police arrived, broke up the socialist meeting, and warned its participants that it was unlawful.
In Bucharest, capital of Nicolae Ceausescu's intransigently antireformist Romania, a similar fate befell veterans of peasant and liberal parties who had stood up to the communists until late 1947.
In Czechoslovakia, the strong socialist and middle-class parties, commanded 60 percent of the popular vote at the time they too succumbed; today, they are strongly represented among adherents of the dissident Charter 77 group. That explains the Prague regime's continued pressure on the group, even while Gustav Husak nods acquiescence to Soviet leader Mikhail Gorbachev's reforms.
The interesting element, however, is the extent to which we are currently seeing the identity of democratic or peasant tradition being invoked, albeit among older hands who have yet to reach the younger generation. The Polish socialists, for example, quickly set up a second meeting and elected a chairman before the police broke it up again.
Of the East Europeans, so far the Hungarians have carried pluralism and reform furthest. They have already tried out multiple candidatures for parliament. And they are changing the law to give noncommunists and ``opposition'' candidates a proper chance in the next vote.
As of Jan. 1, Hungarians will have a ``basic civil right'' in the form of five-year passports on request, to travel anywhere they want, as often as they can afford. For the nonaligned Yugoslavs, this long-held right has been one of the best safety valves for intermittent crises of discontent, like the economic one that theatens their country's living standards today.
Recently, a wide spectrum of supporters and critics of Budapest's government met to discuss economic policy, including two less-attractive Jan. 1 innovations: Western-style personal income tax and value-added tax.
A prominent participant was Imre Pozsgay, a longtime champion of far-reaching reform. ``We shall have to get used to hearing different points of view argued in public,'' he said.
Premier Karoly Grosz, Hungary's new ``strong man'' since May, holds to the same view and said recently that dissident opinions could be helpful. But he also made clear that that did not include challenges to fundamental ideology and constitution.
In the early 1950s, Milovan Djilas - then one of Yugoslavia's top leaders and an ardent reformer - told this writer exuberantly: ``Today, the party line is that there is no party line!'' He was soon to learn that official ideas of reform did not reach that far.
Nor do those of Mr. Gorbachev, or even the progressive Hungarians. Their party line is that pluralism must not be allowed to infringe on one-party writ. But, to make the basic system itself more acceptable, the party must be given a longish rein on domestic issues.
A recent Budapest meeting - this one unofficial and distinctly dissident - was a case in point. It called for sovereignty for parliament and reduced Communist Party power - things Mr. Grosz himself largely favors.
It was the group's call for Hungarian ``neutrality'' that drew a rebuke for the ``extremists.'' A similar demand finally panicked Nikita Khrushchev into intervening in Hungary in 1956 and 12 years later prompted Leonid Brezhnev to act similarly in Czechoslovakia.
Soviet historians may currently hint at a reassessment of Brezhnev attitudes toward Alexander Dubcek's Prague Spring revolt of 1968. If one is, in fact, made, it might suggest Moscow's decision was over-hasty and lacked sound justification. But it is extremely unlikely that it would say anything too embarrassing to the regime that the Russians put in Dubcek's place.
In the age of arms accords with the United States, the allies' loyalty to Comecon, the East-bloc trading group, is just as important, if not more important, to Gorbachev now than the Warsaw Pact. He is, above all interested in a quiet Eastern Europe. This achieved, it can do pretty much what it likes.
In that context, there is some real chance for politically astute - and prudent - pluralism. It might, perhaps, go so far as to ultimately allow Polish socialists and Czech liberals to come into the open without the police butting in.