February 28, 1985

Henry Cabot Lodge, the articulate Massachussetts Republican who was United States delegate to the United Nations, Ambassador to South Vietnam and a three-term Senator, died yesterday at his home in Beverly, Mass., after a long illness. He was 82 years old. At the United Nations from 1953 to 1960, Mr. Lodge, an energetic debater, engaged in ticklish diplomacy, helping bring the Soviet Union into negotiations on the peaceful use of outer space and making behind-the-scenes efforts that helped bring about a cease-fire during the 1956 British, French and Israeli invasion of Egypt. In Saigon During Anti-Diem Coup As Ambassador in wartime Saigon in 1963-64 and again in 1965-67, Mr. Lodge was on hand for the generals' coup that, in late 1963, overthrew the Government of President Ngo Dinh Diem - although Mr. Lodge later contended that he and the Kennedy Administration had not worked for Mr. Diem's overthrow, as has been said in the Pentagon Papers and elsewhere. During his second tour in Saigon, in 1966, Mr. Lodge was involved in a peace effort that proved fruitless at a time when, he later said, United States bombing of North Vietnam was being ''conducted on a largely military basis without enough regard for its political and diplomatic implications.'' He went on to serve as delegate to the Vietnam peace talks in Paris in 1969.

Treasury Secretary James A. Baker 3d promised Congress today that President Reagan would submit a specific tax proposal this spring that would reduce taxes paid by individuals and increase business taxes over all. Mr. Baker's pledge, as the House Ways and Means Committee opened hearings on tax legislation, was the first authoritative notice that the President would endorse and fight for something more than the general principles of what he calls ''tax simplification.'' The commitment added to the political momentum that has been growing in the last couple of weeks toward a complete overhaul of the Federal income tax system. Presidential Announcement Mr. Baker said the President would announce in the next four to six weeks the form his submission to Congress would take. He said it would include ''detailed specifications,'' possibly in the form of suggested revisions in the comprehensive, two-volume proposal made by the Treasury in November or possibly as an actual piece of proposed legislation.

PARIS THERE are few people who can comment on a 60-year career. But Charlotte Perriand, the French designer who was born in 1903 and was, from 1927 to 1937, an associate of the architects Le Corbusier and Pierre Jeanneret, is one who can. Although she doesn't particularly like to. ''Just pretend that I am no longer here,'' said the energetic and youthful-looking Mrs. Perriand recently, speaking French to a visitor as she walked through ''Charlotte Perriand: Un Art de Vivre.'' The retrospective of her work is currently on view at the Musee des Arts Decoratifs in Paris and continues through April 1.

When the opening bell sounded this morning, telephones to the foreign currency traders here at the Chicago Mercantile Exchange were ringing off their hooks, with investors rushing to place orders. The dollar's plunge today and Tuesday, following its leap to new records on Monday, has sent trading volume soaring on the Merc's International Monetary Market. The market is a 13-year-old division of the Merc, where futures contracts for gold, 90-day Treasury bills and West German marks, British pounds, Japanese yen and Swiss and French francs are traded. In addition, the Merc trades option contracts on pounds, marks and Swiss francs.

''What we have to agree is to negotiations in Cairo under the hospitality of the Egyptian President, with American participation, and with a Jordanian-Palestinian delegation without the P.L.O. - without declared members of the P.L.O. - and an Israeli delegation - and let's move ahead.'' - Prime Minister Shimon Peres of Israel. (A1:2.)