What was going on when I was born?

Once, an athlete was revered by the American public, placed on the same pedestal reserved for generals, Medal of Honor winners, movie stars, aviators and more recently astronauts. But to many people - historians, sociologists, educators, and older sports fans - there has been a major change in the athlete's image. Affluence, in many cases the result of bitter collectivebargaining victories by the various player associations, has brought a parade of agents, lawyers and financial advisers into the locker room, shattering the perceived innocence that many fans attached to athletes. In addition, a significant number of athletes, through bad business planning or bad luck, or through plain anti-social behavior, have wound up with their names on police blotters, and even in jail, with increasing frequency. All this has led to a feeling of dissatisfaction among some older fans, who sense the change more than their children do. But that dissatisfaction has not kept fans from ball parks and arenas. While professional basketball and hockey have had some attendance problems in recent years, baseball and pro football generally have not. Nevertheless, owners, commissioners and players say they are aware of the fans' feelings and the circumstances that have led to changes in the personalities of the modern athlete.

The General Motors Corporation today reported net income of $129.4 million for the third quarter, but this was the result of nonautomotive operations. In the third quarter of 1981, by contrast, G.M. had a loss of $468.2 million. The profit came from an income tax credit of $151.5 million and earnings of $214.7 million from the General Motors Acceptance Corporation and Motors Insurance Company, its auto financing operation. The manufacture and sale of cars and trucks produced an operating loss of $53.6 million.

Three sophisticated aircraft, two American and one the product of an Anglo-French collaboration, are competing for a multimillion-dollar French contract that may be the United States aviation industry's last big military sales opportunity in Europe for some time. The contract is to supply France with airborne radar, which would give advance warning of attacking planes, missiles, ships and tanks. The need for such so-called Eye-in-the-Sky planes, military experts say, has been underscored by the recent wars in Lebanon and the Falkland Islands. In Lebanon, the Israelis used airborne radar to guide their fighters, which shot down more than 100 Syrian MIG's, and to locate antiaircraft missile bases, which were then destroyed.

In the beginning it was just Toyota and Datsun. Then Honda earned a place in the American automobile market. Others followed: Mazda, Subaru, Isuzu. This fall Mitsubishi, one of Japan's industrial giants, will try to carve out a segment in the increasingly crowded field of Japanese companies selling cars in the United States. It will not be easy. For one thing, all the Japanese companies are operating under informal - but strict - restraints on the number of cars they can ship to this country. And the proliferation of Japanese brands, along with the increasing number of models offered by each company, makes it more difficult for a new entrant to establish an identity.

The Dow Jones industrial average, the best-known measure of stock market prices, plunged 36.33 points yesterday as concern mounted that the decline in interest rates might be ending. The point drop was the second largest in the history of the Dow, but analysts were quick to say that comparisons were misleading because yesterday's drop represented a much smaller percentage than did the record plunge of 53 years ago. ''The failure of the Federal Reserve to cut the discount rate was the No.1 reason in the hit parade affecting stock prices today,'' said Jack Baker, head of equity trading at the First Boston Corporation. He was referring to widespread expectations that the nation's central bank would announce another reduction in the rate it charges on loans to banks and financial institutions.

A committee of Roman Catholic bishops made public a proposed pastoral letter today asserting that nuclear weapons could destroy the world and calling any first use of those weapons irrational and immoral. ''We find the moral responsibility of beginning nuclear war not justified by rational political objectives,'' the bishops said. For years the United States and allied policy of ''flexible response'' has held that nuclear weapons might be needed to stop an overwhelming conventional attack by the Soviet Union. The Reagan Administration has vigorously upheld that policy. First Statement of Opposition If adopted by the National Conference of Catholic Bishops, the pastoral letter would be the bishops' first sweeping statement opposing nuclear arms. The letter, which will be debated by the nation's 300 bishops at an annual meeting here next month, would also shift concern for arms reduction from the periphery to the core of the church's social ministry.

A controversial proposal under consideration at City College of the City University of New York would put the institution among a select group working actively to promote the teaching of writing skills in subjects other than English. Some faculty members at City College think it is time that writing were taken more seriously. One way to do it, they believe, is to require students to do more expository writing in all courses, not just in English classes. Furthermore, on the assumption that students with inadequate writing skills are not ready to benefit sufficiently from their courses, these faculty members propose to bar students from taking core courses while still enrolled in remedial writing classes. Core courses are those required from a wide number of disciplines - mathematics, science, social sciences and the humanities - to insure the breadth of a student's education.

A Federal board of inquiry will convene in Manhattan tomorrow to investigate the sinking of a fishing boat with the loss of eight lives off Point Pleasant, N.J., on Sunday. Five men drowned, and three others are missing and presumed dead. The investigating panel will be made up of three Coast Guard officers and two members of the National Transportation Safety Board. It will try to determine not only what caused the 47-foot charter fishing boat, Joan La Rie III, to capsize with 22 passengers and crew members just before noon, but also whether the vessel, which was licensed to carry 37 passengers, had complied with safety regulations.

The Exxon Corporation, blaming weak demand and a squeeze on profit margins, said yesterday that its net income for the third quarter fell five-tenths of 1 percent in spite of an unusually large gain from foreign currency translations. Exxon, the world's largest industrial company, said its earnings for the period amounted to $1.07 billion, or $1.23 a share, down from $1.075 billion, or $1.25 a share, a year earlier. Revenues declined 8.3 percent, to $25.33 billion, from $27.61 billion. The company said its operations continued to be hurt by the ''depressed industry environment in evidence throughout 1982,'' the high cost of oil and gas exploration and narrowing margins on its products in Europe. The company buys much of its crude oil from Saudi Arabia, which has kept to its official price level throughout the year, and Exxon said that the declining prices and demand for refined products in Europe resulted in increasingly narrow profit margins.

International Lebanese-Israeli negotiations, with United States participation, have been set and could start later this week in the Beirut area, according to a senior State Department official. The conferees, he said, will seek a formula for Israeli troop withdrawal from Lebanon. (Page A1, Column 6.) Ariel Sharon told an inquiry in Jerusalem that he had not learned that a massacre of Palestinian civilians was occurring in Beirut refugee camps until Friday evening, Sept. 17, more than 24 hours after it had begun and about nine hours after it had been ordered halted by his senior officers. The Israeli Defense Minister spoke at the first open session of the judicial commission that was established to define the extent of Israeli responsibility in the killings. (A1:5.)

Angry members of Parliament accused the Government today of playing down the importance of a breach in security at a topsecret intelligence-gathering center in Britain. The contentions were provoked by a report in The New York Times on Sunday that American officials were asking Britain for details of a security lapse described as "one of the longest and potentially most damaging Soviet penetrations of Western intelligence since World War II." In July, Prime Minister Margaret Thatcher acknowledged that a man identified as Geoffrey Arthur Prime had been charged with violating the Official Secrets Act but she took pains to minimize the importance of the breach in security. Donald Anderson, a member of the opposition Labor Party who questioned Mrs. Thatcher, said today that it seemed she had been "less than frank." The Prime Minister, he said, "should be brought before the House to account for" a possible "cover-up and an attempt to hide the true facts."

Stock prices plunged, reflecting investor concern over the course of interest rates. Pension funds and institutional investors unloaded large blocks of stock, sending the Dow Jones industrial average down 36.33 points, to 995.13, its second-biggest single-day drop ever. Trading volume was moderate, remaining well below recent record levels. The largest stock market decline occurred on Oct. 28, 1929, during the crash that preceded the Depression. (Page A1.) Short- and long-term interest rates rose in the credit markets in what analysts said was a technical correction following the huge declines earlier this month. (D10.) Prices of all three stock index futures fell sharply along with the actual market indexes on the commodities markets. (D12.) The dollar rose to a 12-year high against currencies of major industrial trading partners. Gold and silver prices tumbled. (D12.)