As actors go, Edward Bennett Williams is Brando in a gray pin-striped suit. The next time the lawyer declaims against The Washington Post, someone should film the performance and send it to Cannes for the festival. Olivier would slash his wrists in envy. What a show Williams put on the other night, bringing down the curtain with his sincere-though-hurt plea, "I don't think it's unreasonable to ask people to believe what you say."

Poor EBW. This is getting out of hand. He just wanted to buy a baseball team now that his football team is falling apart. He wanted a baseball team in his hometown, Washington, and the best one available happened to be the Baltimore Orioles. That's where he got into trouble.

Not right away. Williams first thought of buying the team back in the winter. How could he know the Orioles would play sensational baseball and set a team attendance record for the city and, finally, after 25 years' trying, get the Baltimore fans excited?

Back in the dead of winter, hardly anyone cared about the Orioles. The owner, Jerry Hoffberger, was trying to sell the team to local people. He did everything he could, even offering to lend the buyers $4 million. And the local people tried to blackmail the state and city into giving a private business - the Orioles - $250,000 a year.

But no deal was made. The money people, checking the Orioles' profit-and-loss ledgers for a quarter of a century, decided the team wasn't worth the $12 million Hoffberger wanted.

So here came Williams in the dead of winter with his hot idea to buy this franchise that nobody wanted. If no one in Baltimore wanted to buy it, he must have figured, no one would much care if he moved the team to Washington in a couple years.

But then the Orioles really put Williams in a bind. By the time he and Hoffberger completed the negotiations, the team was the best in baseball, running away from the supposed powerhouses in Boston and New York. Now all of Baltimore, even the money people, loved the Birds and here was Williams with his intention to move the team out of town.

Of course, he couldn't say he planned to move a sensational team away from a city that turned out 1.8 million customers (as it seems certain to do).

So Williams has spent the last week telling everyone he has no plans to move the Orioles to Washington, that he has not decided if the Orioles will play 13 games at RFK next year and that he has been - well, sincerely hurt by inferences that his intentions are anything but what he says they are.

Two nights ago he went to Baltimore's Memorial Stadium for the first time this season. His performance was wonderful. Instead of being on the defensive as the Washingtonian who might steal the team, Williams went into the stadium on the offense with both lungs pumping hot air through vocal cords that Redford would kill for.

A Post news story said Williams was leaning toward scheduling the Orioles against the Yankees and Red Sox in series at RFK next year and moving the Orioles to RFK within three years.

Williams vehemently denied the report. In the doing, he pleased all of Baltimore for more reasons than one. He castigated a Washington newspaper, which Baltimoreans love to do, and he seemed to renew his "pledge" to keep the Orioles in Baltimore.

Fact is, Williams was exceedingly specific in his vehement denial. He denied any "plans" to move to RFK within three years.

Because a lawyer in a pin-striped suit denies concrete plans does not mean he is lacking considered intentions. The mastery of semantics can give a man in a lawyer's suit the ability to say things in a way that we ordinary people can hear any way we want to.

If we want to hear EBW say the Orioles will remain in Baltimore, we can hear that. If we want to hear Williams say the Orioles will remain in Baltimore only until he decides it is time to leave, we can hear that.

In 1959 some Washingtonians heard Calvin Griffith say, "The Senators will never move out of Washington in my lifetime." two years later, Griffith's ghost lived in Minnesota with his Senators-become-Twins. Short said, "I didn't buy the Washington Senators to move them," and in 1971 he said, "Washington is my town." People here thought they heard a promise but it must have been a goodbye because later in '71 Short made Arlington, Tex., his town with the Senators-become Rangers.

This town is full of people with ears who heard Edward Bennett Williams, not once but several times, say, "George Allen is the last coach I'll ever hire." Williams said that the last time 18 months before he hired Jack Pardee.

Which explains why, I guess, an old newspaperman once told me, "Here's a rule to live by in this business: Never believe anything you hear and only half of what you see."