"If anybody in this city thinks that those phonies who send him those power invitations will get their hands on him, they are in for one terrible disappointment. As of Monday at 5 p.m. he will essentially disappear as a person who is seen in the scene here in this city."

So saidst Sen. Warren Rudman (R-N.H.) to the Associated Press last week, talking about his good friend David Souter, soon to become history's 105th Supreme Court justice.

But at 5 p.m. yesterday, contrary to Rudman's prediction, Souter didn't disappear, since those who had sent him the ultimate "power invitation" -- George and Barbara Bush -- had gotten their hands on him for a White House swearing-in ceremony. An hour later, after Chief Justice William H. Rehnquist had administered the constitutional oath of office (Souter doesn't become a justice until he takes the judicial oath at 10 a.m. today), Souter still hadn't disappeared. He was too busy being congratulated by some 200 justices, cabinet officers, administration officials and friends as he stood in a receiving line with the Bushes.

The reception that followed the swearing-in was, as one guest put it, "definitely bare-bones." There were no refreshments, no flowers, no frills of any kind in keeping with the president's shutdown of "nonessential" government services. The White House staff on hand was estimated at about one-sixth its normal size.

Bush called it a "reception without a lot of largess," but others there measured largess by the Bush hospitality and the Souter humility. Telling how unexpected the nomination had been, Souter described the day Bush invited him to the White House to break the news. After the initial shock of it all, the Bushes offered him a drink, then the president telephoned Souter's mother. "I want you to know he's okay. We'll look after him," Souter said Bush told her.

"That epitomizes why my sense of gratitude goes beyond anything that could be called official," Souter said yesterday.

According to John A. Butterfield of Chantilly, Martin Van Buren left more than an oval parlor (the White House Blue Room) as his presidential legacy, as Ways brashly noted on Oct. 2.

"What about the man who gave the one word or term that is known and understood around the world?" writes Butterfield. "If there is something in the 'universal language' that people even on remote islands, or in faraway places seem to understand, it's 'OK.' "

Furthermore, Butterfield reminds Ways that Van Buren was "the first standing U.S. vice president who was elected in his own right to the presidency, and the only other one is our current president, George Bush."

Webster's New World Dictionary does indeed ally the colloquialism "OK" with America's eighth president. To wit: "Orig. U.S. colloq.: first known use (March 23, 1839) by C.G. Greene, editor, in the Boston Morning Post, as if abbrev. for "oll korrect," facetious misspelling of all correct (cf. Am. Speech, Vol. XXXVIII, No. 1): popularized by use in name of Democratic O.K. Club (1840), in allusion to Old Kinderhook, native village of Martin Van Buren, whom the Club supported for a 2d term."

All of which is OK.

What's questionably OK is the mischievous way Butterfield waits until the very end of his letter to identify someone else who hails from Kinderhook, N.Y.

Himself.

Best-selling author Mildred Kerr Bush -- Millie to her friends -- is responding favorably to steroid therapy since being diagnosed with lupus this summer, according to Anna Perez, Barbara Bush's press secretary.

Perez says that the Bushes' English springer spaniel is on prednisone and that contrary to rumors she is not terminally ill.

Veterinarians describe the disease's symptoms as lameness, blood disorders and changes in the skin and internal organs. It can be diagnosed either by blood tests or skin biopsies. If left untreated, it can be life-threatening.

William Swartz, a McLean veterinarian, says lupus is relatively rare -- fewer than 1 percent of dogs with skin disease may have it.

Moving Ahead: Rosalynn Carter, 63, who was named a distinguished fellow by Emory University in a new program that supports academic studies of women in public policy. Called the Rosalynn Carter Honorary Fellows in Public Policy and Global Affairs, the program offers fellowships for graduate studies, undergraduate internships and a distinguished lecture series. Elizabeth Fox-Genovese of Emory's Institute for Women's Studies said the former First Lady will participate as "mentor and intellectual and personal leader" for those in the program. "She is very sharp on a wide range of issues," she added. Mrs. Carter, in a statement, said the programs "will demonstrate the value of public service and will inspire future generations to pursue a career in working to improve the quality of life for both men and women."

Moving Up: Timothy J. McCarthy, 41, the Secret Service agent wounded in the 1981 assassination attempt against President Reagan -- and credited with saving his life. McCarthy takes on a new assignment as special agent in charge of the agency's Chicago office, which is being expanded to investigate fraud within the savings and loan industry. "For me," said McCarthy of his new duties, "this appointment represents the pinnacle of my career."

Moving In: The National Park Service opens the recently renovated guest house at the Eisenhower Historic Site at Gettysburg College Sunday and dedicates a new flower garden that the National Trust of Scotland has donated. The occasion is the 100th anniversary of Dwight D. Eisenhower's birth, a weekendlong celebration featuring an all-star cast that will include Gerald Ford, Bob Hope and David Eisenhower.

Barbara Bush will be playing herself when she appears in a public service announcement at the end of the Oct. 18 installment of ABC's daytime soap opera "All My Children." She will urge viewers to get in touch with the National Bone Marrow Registry after she describes the simple, painless test for determining bone marrow compatibility. The announcement will augment the show's current story line in which a young leukemia victim's survival depends on receiving a bone marrow transplant.

A Los Angeleno who had long loathed its smog, fumes and shopping malls, Robert Redford was finally spurred into the environmental battle by the threat of a Utah superhighway that would have been a boon to trucking interests but would have meant virtual extinction to some of the wildlife in the area.

Redford, who was in Washington last week, says he took up the cause in 1969 when a group of his neighbors in the Provo Canyon region near his Sundance, Utah, resort came to him for help. They had been unable to get officials to listen to their complaints about a plan to upgrade an existing road to a superhighway. They soon learned they were bit players in a rerun of an all-too-familiar scenario.

"It turned out that the elected officials had a particular interest in putting in the road," Redford said after delivering a lecture at the Smithsonian. "One guy was the concrete guy, and the other one was the asphalt guy. The more I became educated, the madder I got. The road would have destroyed a stream by the existing road, and all the fish and wildlife in it. I saw it as a microcosm of everything going on all around the country and that started me off."