IN 1971, I.F. (Izzy) Stone, editor and publisher of I.F. Stone's Weekly, printed his last issue and announced his retirement. He reportedly joked that "covering the universe in four pages" every seven days was too tiring for a man his age. Then too, he had developed some heart trouble.

Stone, now 75, did not spend the ensuing years flipping through old scrapbooks or refinishing the rec room. Instead, he accidentally turned into a classical scholar-journalist, in a field he probably occupies sui generis, alone. In doing research on the history of free speech, Stone got stuck in the 17th century, which he couldn't make sense of without dropping back to study the Reformation, which pushed him further back to "the Medievals," and thence to Athens. Suddenly Stone found himself knee-deep in Greek lexicons, reading Homer and "case-querying" the trial of Socrates, Athens' most famous philosopher. He also found himself a news story. Stone calls it "my last scoop."

Tonight at 8, Stone will deliver the last segment of that "scoop," titled "Retrying Socrates: What Plato Doesn't Tell Us," at Georgetown University's Gaston Hall. If the last two lectures are any indication, ticket sales will be brisk and the hall packed. Perhaps you haven't given the trial of Socrates much thought lately, given the fast-breaking developments in El Salvador. But when Marcus Raskin, codirector of the Institute for Policy Studies (which has sponsored Stone's talks), introduced him at the first lecture, Stone lost no time in establishing his subject's relevance.

Stone walked briskly toward the podium like a small, bespectacled cherub. He smiled at the crowd and said, "There's a certain irony here. There is no one that the right-wingers and paranoids in Washington would rather give hemlock to than Marc Raskin." The crowd, many of which were old enough to have been blacklisted during the McCarthy era, roared. Then Stone got down to business.

"I'm not here to debunk Plato or Socrates. Socrates' trial as recounted by Plato is the loveliest of Greek poems. It is also, if I may say so, a masterpiece of evasion."

Having sounded a trumpet that would have shattered Emerson's eardrums, Stone blew another for good measure. "The salient fact about the Socratics, of which Plato was one, was their contempt for democracy." Stone was not denying the contribution these philosophers have made (Alfred North Whitehead once said that "all philosophy is a footnote to Plato") but the facts are, said Stone, that both Socrates and Plato were insufferable elitists. In Athens, where "even the poorest citizens were honored," Socrates viewed the common man as part of a herd that ought not be consulted anymore than a shepherd consults his flock.

That Socrates and Plato were snobs is not exactly fresh news from the Peloponnesus. Classical scholars have long known that both of them turned up their noses at the middle class, which they considered too dull-witted to define the ultimate meaning of life, let alone run a good utopia. But what Stone brings, with all the undiluted enthusiasm of a new guy on the news floor, is new questions.

How could Athens condemn its most famous philosopher to death? (The untold case for the prosecution.) How could Socrates have won his acquittal? ("Or to be funny about it," said Stone, "how the ACLU could have gotten him off.") What were the "hidden horrors" of Plato's utopia? (Stone clearly thinks the Athenians were saintly in their tolerance of Socrates and his gang.)

"I lament the trial of Socrates," said Stone, but in the light of his research, he said he understood how it could have happened. "The trial in 399 B.C. wouldn't have come to pass if there had not been three political earthquakes in the decade before. In 411 and 404, the oligarchs overthrew democracy and temporarily gave Athens the most corrupt and brutal governments it had ever known. The oligarchs were overthrown by a coalition of the middle-class and working-class elements. The hard-core aristocrats were allowed to withdraw to Eleusis, but the Athenian democrats heard that they were training mercenaries to overthrow Athens again. In 401, the Athenians marched on Eleusis, killed the leaders and brought about a final reconciliation.

But then, once democracy was restored, there was Socrates, back at the same old stand, followed around by the same rich kids, preaching his anti-democratic, negative dialectic." Perhaps, Stone suggested, for the Athenians, enough was finally enough.

Two hours passed like a snap of the fingers.

As he slowly built his arguments and conclusions, like a curbstone lawyer who just happened to drift into the crowd hanging out at the Agora (assembly) when Socrates was being tried, two thoughts occurred. Stone, at the age of 75, was onto something, and Stone, with the unabashed delight of a philatelist who has been invited to spread out his stamp collection, was having fun.

A sampling of precious "Stones":

* "Socrates had no vision of the virtue of the unlettered. When the pope in Guatemala said yesterday, 'When you torture man, you torture God,' the pope was speaking of dignity. But there is nothing of this in Socrates. He never speaks of the poor."

* "It's hard to understand how the Socratics could be so in love with Sparta. It was an illiterate, military barracks of a town. There was no art, no poetry and philosophers weren't even allowed in. Homosexuality was encouraged. All the Greeks were pederasts, but in Sparta it was encouraged since men would fight more courageously at their sides. But the aristocrats loved Sparta because it was a stable society. It was also a dead society."

* "Plato was like a torpedo flatfish. He immobilized people. A negative dialectician, he could knock out other people's definitions without providing any of his own."

* "Solon was the FDR of early Athens."

* "Socrates called himself 'the gadfly of Athens.' But what the hell kind of a gadfly was he when he never spoke up against slavery, or against the Sicilian expedition?"

Stone asked that question of Socrates more in sorrow than in anger, as if a colleague had let the society of gadflies down. Stone once provoked Vice President Spiro Agnew, who called his Weekly "another strident voice of illiberalism." David Eisenhower boycotted his own Amherst graduation because Stone was to deliver the commencement address. An unfashionably early protester against the Vietnam war, J. Edgar Hoover, Richard Nixon and the military-industrial complex, Stone buttressed his opinions with hard work, eschewing the "highly placed sources" route to the truth, burrowing through mounds of public records to pick up telling discrepancies and double-speak testimonies to support his views.

He used these same methods to document his views about the trial of Socrates. He burrowed into Aristophanes' plays, Plato's dialogues, the writings of Xenophon and Homer's poems; when Stone read the original Greek version of Plato's "Phaedo" (Socrates' farewell to his friends), he was so moved by the final pages that he burst into tears. His lectures are full of planned digressions, for which Stone asks the audience's forgiveness, so he can fully present his case.

Come the questions from the floor. "Brickbats are invited," said Stone. "Sometimes they save time."

"Is the word 'homosexual' used by you as a derogatory word?" asked one Greek member of the audience. Stone apologized. "The Judeo-Christian world had some very hard references to homosexuality. The Greek society was free of those prejudices. I was wrong to make my slighting remark."

Each question revealed the full scope of Stone's research. Like a dry-goods salesman, he pulled bolts of material from the shelf upon request and unfolded his thoughts like a tapestry before one's eyes.

In the end, however, Stone understands the difficulty of doing research in antiquity. "One has to be very scrupulous, take nothing for granted, and don't start out as a smart a--" when examining ancient history, he said. "Antiquity is like a gigantic jigsaw puzzle with most of the pieces missing. We have to be tolerant of different views and recognize that Whig history, Tory history, Marxist history--each of them can enrich our view."

Stone, at the conclusion of his second lecture, was still as fresh as a Mediterranean sea breeze. The rigors of research clearly had done him good. In his characteristic high, piping voice, he concluded with a brief pitch for taking history seriously.

"History is an art and also a tragedy because it deals with men striving to fulfil themselves, usually within very strict limits. But some men have acted with courage, vision, passion and compassion. Ultimately, history is a mystery worth our meditation. Take it or leave it, as you like it."

Thus spake Izzy Stone. The crowd gave him a standing ovation, knowing he might not pass this way again. Then the philosopher-journalist "gadfly" of Washington pulled on his rubber galoshes, put his arm through his wife's arm and went home.