About five years ago I went to a university library in my neighborhood to borrow a few books on Greek literature. Behind the rows of books where antiquity lay quiet that afternoon were some partitioned desks for the studious. One of these was I. F. Stone, up to his well-known bushy eyebrows in out-of-print texts of the classics and reading them with monastic attentiveness.

I left Stone undisturbed. Days later I came upon him while he was waiting for the evening bus outside the campus gate. Washington's, and perhaps the West's, most alert sniffer of official lies and a journalist who went his lone energetic way from 1953 until 1971 in "I. F. Stone's Weekly" explained why in his early seventies and semiretirement he was holing up in the recesses of libraries. Socrates, he said. Stone was starting his study of the philosopher by learning Greek as it was spoken in the ancient city-states.

Charged up, as if the politics of the Parthenon and Acropolis were breaking news and this morning's front pages had missed it, Stone spoke of the joys of going back to primary sources. They're trustier, he cracked, than Washington's reliable sources.

Now, at 80 and unslowed by recent health troubles, Stone has put his own scholarly book, "The Trial of Socrates," on the shelves. As a reporter, Stone was the rare icy investigator who trailed after facts by scouring basic texts. As a civil libertarian, Stone brings the same ire to the abuses of fifth- and fourth-century democracy as he does to those in modern nations. Covering a free-speech trial that occurred in 399 B.C. and for which no court transcripts are available tested Stone's investigatory skills to the limit. For 60 years, journalism had no one like him. The same is now true for classical scholarship.

Stone describes Socrates as "the most talkative Athenian of his time . . . the man who made talk his life and monument." Much of the Socratic noise, as found in Plato's "Gorgias" and Xenophon's "Memorabilia," came in antigovernment attacks, on both Greek democrats and conservatives. Of Pericles, one of the state's most revered democratic leaders, Socrates says: he left the masses "wilder than when he took them in hand. . . . We know of nobody who has shown himself a good statesman in this city of ours. I think I am one of the few, not to say the only one, in Athens who attempts the true art of statesmanship."

That was not, Stone comments wryly, Socrates' "most modest moment." But it reflects the Greek's thinking as "a loyal monarchist." Socrates prefers leaders who are shepherds who see that their "sheep are safe and fed." Stone parries: "The good shepherd does indeed see that his flock is safe and fed. . . . But the ultimate purpose of the shepherd is to shear the sheep for their wool and eventually to sell them for mutton. The herd is destined for the meat market, and the sheep are not consulted by the shepherd when he decides their time has come. The lesson the Greeks drew. . . is that the sheep cannot trust their shepherd, nor a community entrust itself to one man's absolute will, however benevolent he claims his purpose to be. They preferred to become a polis rather than be treated like a herd."

Despite that ideal, the democrats put Socrates on trial for his intellectual attacks on democracy, a contradiction that horrified Stone. The trial, he writes, "was a black mark for Athens and the freedom it symbolized."

Then there is Socrates, of large ego and small heart. Like Tolstoy, Gandhi and many other men hailed as great outside the home but who were often brooding despots with their wives and children, Socrates was curt and unfeeling to his devoted wife Xanthippe.

Stone reports those details and a Mediterranean's worth of others. "The Trial of Socrates" is a love story, a story of one reporter's ardency for study. At the University of Pennsylvania, which he left before graduation for newspapering, Stone was a philosophy major. His book can be taken as a belated thesis, 60 years in the making. No one ever said investigative reporting was a quick art.