Maybe you thought you had the last word on social climbing exclusively from Post reporter Stephanie Mansfield's amusing 10-step do-it-yourself guide in the Post Magazine Jan. 2. It was the one that began, "You weren't invited to Pamela Harriman's for eggnog. You didn't get a call from Henry and Nancy Kissinger. . . ." Not so. On the same day, a Philadelphia Inquirer feature began: "You weren't invited to Henry McIlhenny's for eggnog. You didn't get a call from John and Barbara Eisenhower. . . ." And, a week later, the Wilmington News-Journal addressed readers who "weren't invited to Bunny du Pont's for eggnog. Ned and Carroll Carpenter didn't call. . . . "

Recall that your New Year's resolve was "to get your social act together," and Miss Mansfield's admonition was: "connive and strive your way to the top. Stop at nothing. Be ruthless. Be shameless. Be yourself." All this and more was lifted verbatim from Miss Mansfield's text, including, when discussing vacation places "practice saying, 'The Hamptons have become simply intolerable.'" More intolerable to Miss Mansfield and Post editors is the evidence of plagiarism.

As clients of the Los Angeles Times/ Washington Post News Service, the Inquirer and News-Journal were entitled to Miss Mansfield's article, provided the service was properly credited; better still, to include the writer's byline. After substituting Philadelphia names and other changes, the Inquirer credited (incorrectly) the "Washington Post Service," lending the appearance of a Post reporter writing the story from Philadelphia. Features editor Murray Dubin acknowledges being "not completely comfortable" and wishes "there had been a better solution." Agreeing that "it looks awkward" to have identified The Post after changing what was sent, he waffles on a question about breach of ethics: "I'm not sure . . ." Meanwhile, Inquirer readers have been given no explanation of the story's origins.

Deception was carried further at the News-Journal when a fictitious byline-- "Mary Anne Grayson, Special to the News-Journal"--was put on its version. Executive Editor Sidney Hurlburt admits to "eating crow" and being "painfully aware" that "too much was appropriated." Miss Mansfield's piece was given to two feature writers to adapt to the Delaware social scene. They agreed to do it, provided their names did not appear on the story. Thus, the nom de plume. In exquisite irony, some News- Journal readers, saying the article looked familiar, wondered whether the paper had bought plagiarized material.

The paper ran a "corrective" a day or two later. In a longer explanation Jan. 16, Public Editor Harry F. Themal observed correctly that all newspapers buy a lot of syndicated material that subscribers are free to use entirely, to cut for space or to insert something of local relevance. (Many newspapers, including this one, often fail to give specific credit to news agency material). Citing a dictionary defintion and granting that readers were "certainly deceived into thinking this material was original," Mr. Themal concludes that this case "borders" on plagiarism. The view here--like Gertrude Stein's on the rose--is less equivocal. Otherwise, definitions are without meaning.

Addenda:

When it was disclosed that the Justice Department was considering a recommendation to indict Rep. Charles E. Schumer (D-N.Y.) for alleged misuse of funds while serving in the state legislature, The Post carried a long bylined story on page one. When Justice announced a week later it would not pursue the case, editors ignored a piece by the reporter who wrote the initial story, relying on a four-inch news service item and putting it on page five.

The same unfortunate tendency was demonstrated when the White House Office of Management and Budget "cleared" members of the Legal Services Board of improperly charging excessive consulting fees and other extravagances, allegations that made front-page material several times. The clearance story, although written by the same reporter, was also relegated to an inside page.

A Jan. 13 story on the nomination of Margaret Heckler to be secretary of health and human services gratuitously referred to the former congresswoman as "a Roman Catholic with three children . . . opposed to abortion." Inexcusable that, and a wonder how it passed the copy desk.