What was going on when I was born?

France announced today that it would remove about 25 percent of its troops serving with the four-nation force here. The announcement, made simultaneously here and in Paris, added to the nervousness of Lebanese in the capital about the future of the Western presence that is supposed to guarantee their security. An official statement said that at the end of the month, 482 troops from the 1,750-strong French contingent would be withdrawn from Beirut and returned to French positions with the United Nations force in southern Lebanon. No Full Pullout, France Says The reduction, a French spokesman in Beirut said, will not affect the overall number of French soldiers in Lebanon, but the force in Beirut will be cut back by a quarter. The spokesman denied that the move was the precursor of a complete French pullout from the multinational force, also made up of troops from the United States, Britain and Italy.

THE doctor suffered what, strictly speaking, was a minor accident, the kind that is surprisingly common in hospitals and offices. While suturing a patient, his hands slipped and he jabbed himself with the needle. But this accident could not be taken lightly. The patient had the deadly disease known as acquired immune deficiency syndrome (AIDS). And the physician nearly panicked. ''I felt I was sure to get AIDS, sure I'd die from it,'' the young doctor recalls now. ''Then I assured myself that I was not the first person to stick himself and that no one else has gotten AIDS that way. Still, when I had a cold or wasn't feeling well, it was in the back of my mind.'' Another reassuring factor for him was the presence in the hospital of senior doctors who had dealt with every manner of infectious ailment and lived to tell the tale.

Economic Analysis PARIS, Jan. 2 - Two conflicting views among economists about the dollar's future are raising doubts about the durability of the world recovery as it enters its second year. Right now, the dollar is showing phenomenal strength. But some economists fear that international confidence will eventually snap, forcing United States officials to push up interest rates again to halt an inflationary plunge in the dollar's value as foreign capital flees the country. If this were to happen, this view maintains, economic growth in the United States would grind to a halt, and with it, the single most powerful engine propelling the rest of the world toward recovery. Others, however, fear that without a radical change in United States economic policy, the dollar will remain overly strong, gradually bankrupting a big slice of American industry as it attracts cheap imports and prices United States goods out of foreign markets. According to this scenario, it is support for free trade that would then snap as the United States retreats behind tough protectionist measures.

AN extensive new survey indicates that the use of cocaine continues to increase dramatically in the United States and that the problems associated with it are far worse than many people had believed. These conclusions are drawn by researchers who have interviewed or talked briefly with thousands of callers on a ''cocaine helpline,'' a telephone service set up to offer advice to the nation's five million cocaine users and to people asking questions about cocaine-related problems. The researchers now report receiving about 1,000 calls a day nationwide. Medical and social difficulties appear to be particularly acute among people who take the drug intranasally - that is, by inhaling it through the nose. About half of the people interviewed who said they took the drug intranasally reported feelings of paranoia and panic, considered themselves to be addicted and experienced withdrawal symptoms when they stopped using cocaine.

Fenno Heath stood on a near- empty stage and addressed the hundreds of volunteer singers seated in the audience. He waved his arms, the audience rose to its feet, and he coaxed the singers through the opening chorus of Handel's ''Messiah.'' ''This theater has probably never seen such a performance,'' Mr. Heath, director of the Yale Glee Club, told the crowd at the Shubert Performing Arts Center the other day. The ''Do-It-Yourself Messiah'' was indeed a departure for the theater, which began presenting holiday concerts several weeks ago. For more than 60 years, before it closed in 1976, the center was known as the Shubert Theater and was famous as a place to try out Broadway shows.

Reflecting the growing economy and severe cost-cutting, corporate profits for the fourth quarter are expected to show another solid advance, economists and industry analysts say. Compared with a year earlier, when profits bottomed out at the trough of the recession, the gains should be particularly impressive. In 1982, ''companies were very concerned about their financial survival and took many measures to reduce costs,'' said M. Kathyrn Eickoff, executive vice president at Townsend- Greenspan & Company, the economic consulting firm. ''With breakeven points dramatically reduced, this year they are getting the benefit, and that is reflected in bottom-line gains.''

Democratic and Republican leaders in the House said today that a reassessment of United States policy in Lebanon was vital. The statements, by the House Speaker and the minority leader, came amid increasing expressions of concern in Congress over the continued deployment of 1,800 marines in the four- nation force in Beirut. Representative Robert H. Michel, Republican of Illinois, the minority leader, said of the Marines' position, ''We're just so darned boxed in, how can we influence anything?'' Reassessment Held 'Essential' Mr. Michel, in a telephone interview from his home in Peoria, said a reas sessment of the American policy was ''essential.'' He said that he did not favor an immediate pullout of American troops, as had been reported, but added, ''You just can't keep going on forever and ever.''

While 1983 was a good year for stocks in general, it was an extraordinarily good year for a few stocks, and an unspeakably bad one for several others. The Dow Jones industrial average posted a 20.3 percent gain in 1983, but that was as nothing compared with the 25-fold rise in the stock of Dento- Med Industries, an over-the-counter company that has developed a new type of false teeth. Dento-Med had the best percentage gain among the top 10 stocks in New York Stock Exchange, American Stock Exchange and over-the-counter trading. Leading the list of stocks upon which fortune did not shine last year was the Baldwin-United Corporation, the piano maker turned insurance conglomerate, which was forced to file for reorganization. Its stock fell a staggering 91.9 percent.

The 207th session of the New York State Legislature convenes in Albany tomorrow amid an improving economy and the increasing contentiousness of an election year. The session will formally get under way with Governor Cuomo delivering his second State of the State Message in the Assembly chamber. Both the Governor and legislative leaders say the session will be dominated by debates on how to improve education, how to allocate low-cost hydroelectric power and how to promote economic development in the state. Little Agreement on Methods But despite agreement on goals, there appeared to be little agreement on how to attain them and how much they would cost. While Senate Republicans are talking about cutting taxes this election year, the Assembly Speaker, Stanley Fink, said he would support a tax increase if necessary to improve ''the delivery of pedagogical services.''

Five months after Diana Ross said she would pay for a playground in Central Park with television proceeds from her concert there, her production company has sent New York City only a financial statement showing no revenue and no profits, according to park officials. The playground, to be named for Miss Ross and to be built at 81st Street near Central Park West, was to be financed with a 7 1/2 percent share of the profits from television broadcasts of the concert, according to a letter of agreement with the singer's film company, Anaid Film Productions. The letter did not guarantee a specific amount of money. The agreement, however, was a condition set by the city for approval of the concert.

TUESDAY, JANUARY 3, 1984 The Economy Corporate profits advanced solidly in last year's fourth quarter, according to industry analysts and economists. Townsend-Greenspan & Company, for example, says companies will report a 32 percent gain in after-tax earnings from a year earlier, when profits bottomed out in the trough of the recession. The improved results reflect continued economic growth and corporate efforts to hold down costs, the analysts say. (Page D1.)

EACH year at the University of Connecticut about 600 undergraduates, majoring in fields ranging from business administration to zoology, take an English course in which they write rhymes to be recited while skipping rope, compose one-act plays for youngsters and read some of the best literature written for children. The size of the course's enrollment reflects the rising interest in children's literature at colleges and universities throughout the country. After a long struggle, the subject is establishing itself as a discipline deemed worthy of the serious concern of scholars. Six journals are now devoted to the field and a rapidly growing body of research embraces works written for children by, for example, Maurice Sendak and E. B. White. Last summer, the National Endowment for the Humanities sponsored a conference for the country's authorities on children's literature.