Normally sensible Italians are saying some far-out things about the kidnapping of former prime minister Aldo Moro by the Red Brigades. Alberto Moravia, the great novelist, wrote in the Corriere Della Serra of Milan that the act proved "the total emptiness of the absurd."

Leonardo Sciassia, the Sicilian novelist, said in La Repubblica of Rome that "everything that happens seems to be at random. Events are connected by a chain of accidents . . . Reality imitates imagination."

The most professional of editors, Arrigo Levi of La Stampa in Turin, wrote that the Italians should immediately elect Moro president of the republic for the term beginning next year. He added that the nine European prime ministers should make Moro an honorary member of their group.

Such ravings denote a feeling - easier to sense than analyze - that the kidnapping has touched off a political earthquake. The basic Italian way - the way of waiting out events or muddling through - has been challenged. Particularly in doubt is the classic technique for co-opting revolutionaries into middle-class society by administering small doses of la dolce vita.

That technique, effective before in housebreaking first the radicals and then the Socialists, looked like a winner again when the Italian Communists under Enrico Berlinguer began moving toward a "historic compromise" or coalition with the ruling Christian Democrats. The majority wing of that party, led by Moro, responded with creeping historic compromise.

First, a Christian Democratic government under Giulio Andreotti took office last year thanks to abstention by the Communists, who had been allowed a voice in its economic program. Last month another Andreotti regime was installed with the support of the Communists, who had played a larger role in framing its program. Eventually the Communists might have become part of the majority, and even had ministers in the government.

Along the way, however, the Communist Party was being made to pay a stiff price. It has had to endorse a general tightening of economic conditions, which raised unemployment. It has just been obliged to come out for wage restraint. It was going to be asked to support labor mobility (meaning the right to fire), and cuts in public services, and tougher police action, and the defense budget and the NATO alliance.

Perhaps responsibility for hard times and collusion with the center will cost the Communists votes in the next election. Moreover, it is possible that if they did eventually come to power they would have lost their revolutionary spark.

The kidnapping, however, dealt what is perhaps a death blow to creeping historic compromise. First of all, it deprived the Christian Democrats of the leader best able to manage the process. Already, many-sided factionalism is asserting itself within the party in competition for the elections to the presidential post next December. Hardliners who would provoke a direct fight with the Communists on such losing issues as divorce and abortion are coming to the surface.

In addition, the kidnapping demonstrated that taking the Communist Party into the camp of middle-class politics would not end revolutionary violence. There remains an indigestible residue of all-out Marxist-Leninists who plunge into terror and violence the better to expose the regular Communists as reformers who have sold out to the system. That describes exactly the genesis of the Red Brigades who kidnapped Moro.

An ironic result is that the Communists are strengthened. Not only is the inefficacy of the police and the regime exposed; but also the Communists come on as the law-and-order party, denouncing the Red Brigades in the strongest terms, and demanding early entry to a government of "national emergency."

What will happen now, nobody knows. But there is a general feeling that something, finally, must happen. Politics Italian-style - the politics of doing almost nothing - seems to be on the way out, which is why so many sane people are uneasy.