What was going on when I was born?

Charges that New York City police officers have abused and brutalized blacks will be presented tomorrow at a one-day Congressional hearing in Manhattan. Mayor Koch says the hearing is politically motivated. But a group of black leaders predicts the hearing will demonstrate a problem it says has been made worse by the Mayor's rhetoric. The issue has become so emotional that the Koch administration has been gathering evidence and witnesses for weeks in its effort to show that both racial tension in the city and the unwarranted use of force by the police have declined. Black Captain Appointed In addition, Police Commissioner Robert J. McGuire last month appointed a black captain, David W. Scott, to command Harlem's 28th Precinct. ''I've got to deal with perceptions,'' Mr. McGuire said.

It is common knowledge among foreign visitors to the United States that Philadelphia has more Cezannes on permanent public view than any other city of its size. Why this should be, few strangers can say. But when they count up the 65 and more Cezannes in the Barnes Collection, and add to them the 28 Cezannes in the Philadelphia Museum of Fine Arts, their heads spin. If we calculate that there are also an undisclosed number of Cezannes in Philadelphia private collections, we realize that the city has something to boast about, even though boasting in Philadelphia is reprobated as bad form. Surely - every curator must say to himself -''Cezanne in Philadelphia Collections'' is an exhibition that comes ready-made and only asks to be hung on the wall? In a rational world the Barnes Collection's Cezannes would be integrated for the occasion with those of the museum. Private collectors would be asked to join in, and he would be a churl indeed who said no. This plan would make particularly good sense in July and August, since the Barnes Collection is closed to the public during those two months.

We like to eat out and drive fast cars, We take our dates to expensive bars Sing hey, hey we're the MBAs Having fun earning twice our age. - MBAs theme song By JOHN J. GEOGHEGAN 3d FAIRFIELD PETER WIRTH is the Clark Kent of Wall Street. By day the mildmannered Mr. Wirth commutes from his Fairfield home to his job as investment banker at Keefe, Bruyette & Woods Inc. By night he undergoes a transformation. Mr. Wirth, also known as Manny Hanover, then becomes the lead vocalist, lyricist and concept man for a new pro-business rock group called the MBAs.

THE PHILOSOPHER'S PUPIL By Iris Murdoch. 576 pp. New York: The Viking Press. $17.75. IN Plato's allegory of the cave, men are imagined as dwelling underground, necks and legs fettered so that they cannot look around to see the source of light but are condemned to see only passing shadows, to which they give various names and meanings. This is our commonly experienced reality. If an individual was freed of his shackles and forced to confront the source of light, he would be dazzled and blinded and might respond by preferring the shadows he had seen before, believing them to be clearer. Only by force can the shadow-enthralled be awakened to the genuine source of light -for Plato, the idea of the good, for Platonists of more recent times, God.

Will the Spending Last? American consumers appear to have led the country out of the recession at last. Three straight months of solid sales gains say so. But will they remain strong-hearted? Is the euphoria overoptimistic? And what could turn consumers elusive again? The answers, say economists, are: Yes, no, and unemployment, inflation and interest rates. But they add that, just as the upturn was a long time in coming, a reversal will not happen overnight.

For decades, much of the Waldorf-Astoria's splendid Art Deco interior details were covered up as various areas were redecorated and modernized. As part of an ongoing restoration project that has already left its mark on the Park Avenue lobby, the hotel's balconied grand ballroom is being refurbished in the 1930's style.

State Department officials said today that Soviet authorities had given the last of the Pentecostals who spent nearly five years in asylum in the United States Embassy in Moscow permission to emigrate. Some officials say the move is connected to the forthcoming conclusion of the East-West conference in Madrid. Max M. Kampelman, the chief American negotiator at the Madrid review conference on East-West security, cooperation and human rights, also referred to Soviet actions in a statement explaining why the United States had decided to accept a compromise document to conclude the three-year-old Madrid meeting. He said the United States ''noted and welcomed a few gestures from the Soviet Union and will continue to encourage further such steps.'' He added: ''We hope there will be other developments in response to our concerns.''

LEONIA POLICE CHIEF Paul W. Dittmar waved the car to the curb and Officer Ronald C. Castronova approached it. With his flashlight, he probed the driver's face, especially his eyes, and the vehicle's interior. ''Step out of the car, please,'' Officer Castronova said. The driver, about 25 years old, stood under a canopy of maple trees at the edge of Grand Avenue in this Bergen County community. Red flares, whirling police car lights and yellow signs slowed traffic as it neared the police roadblock.

''Not to be too shy. Too pretentious. But if there is one thing left, I want love.'' The speaker is Roland Petit, the French choreographer and director, who has been provoking and charming ballet audiences for nearly 40 years now. ''The theater is a way to make love with the others, with the audience,'' he continues, ''with what you know and don't know, with the abstract and the realistic.'' The tone is that of a boulevardier caught up in an almost solemn moment, full of an insouciant warmth that is at odds with the chrome and mirrored surfaces of the Manhattan hotel bar where he speaks, and with the formidable venture Mr. Petit is about to embark on. A season at the Metropolitan Opera House, where his Ballet National de Marseilles opens tomorrow for two weeks, is quite an undertaking, even with the services of such superstars as Natalia Makarova and Rudolf Nureyev. But Mr. Petit, a choreographer of international reputation and certainly the best known of contemporary French dancemakers, has been described as a kind of successor to Serge Diaghilev - because of his early ballet collaborations with fashionable designers, composers and writers.

Congress, if it follows its newest budget plan, will put a stop to the domestic budget cutting of the first two years of the Reagan Administration. In 1981 and 1982, Congress cut spending in a broad range of nonmilitary programs, including Medicare, Medicaid, food stamps, energy, education and job training, enough to shave $223 billion from projected deficits for the fiscal years 1983 through 1986, according to the Congressional Budget Office. In the Congressional budget resolution for the fiscal year 1984, adopted last month, there is no reduction in nonmilitary spending over the next three years, newly revised estimates by the Budget Office show. Only with slight reductions in Social Security expenditures, enacted earlier in the year as part of a rescue plan, has Congress pared nonmilitary spending. Stalemate on Fiscal Policy Because the Reagan Administration stands firm on the need to increase military spending, this halt in nonmilitary spending cuts leaves Congress and the Administration in a stalemate. It is now likely that neither side can achieve the spending reductions overall that would shrink future budget deficits. Many economists contend that large deficits will force up interest rates and slow the economic recovery next year or in 1985.

THE wild chirping of the least tern fills the air of a flat, grassy beach in Islip. The area, which is dotted with look-alike least terns of various sizes, is a perfect nesting site - so ideal, in fact, that it is encircled by a low-voltage fence that deters predators: a clear indication that this haven was formed by man and not by some miracle of nature. The beach's bird population is made up largely of decoys, and the bird sounds are piped up from stereo equipment buried deep in the sand. This environment-within-an-environment was constructed inside the 200 acres of swampy salt marshes, beach and flatland that make up the Seatuck National Wildlife Refuge in an effort to insure that the terns will not disappear from Long Island. The least terns, medium-size birds that feed on small fish but that lay their eggs in sand, have been nesting on the Island for as long as anyone can remember, but this year they were declared an endangered species by the State of New York.

Washington and Athens shook hands last week on an agreement extending the American military presence in Greece for at least another five years. Differences in interpretation made it sound like each side got more than the other side said it gave. Socialist Prime Minister Andreas Papandreou, who campaigned in 1981 that he would end the ''strictly colonial'' arrangement under which the United States has maintained bases in Greece since 1953, said he had done just that. He spoke as if there were no question about the Americans packing up in 1988. Describing the agreement as ''a timetable for the withdrawal of the bases,'' he said they would be dismantled within 17 months after the five years were up.