Lunch with director Jonathan Miller is in turns a testing lecture on philosophy and literature, a hilarious stand-up routine, a somber poetry lesson, a doleful diatribe against trends in opera production, and a lugubrious harangue against celebrity culture and vulgarity. Above all, it is a superb one-man show.

Mr. Miller, here to finesse his production of Domenico Cimarosa’s “Il Matrimonio Segreto,” which opens today in a short run at the Brooklyn Academy of Music’s Harvey Theater, cannot contain his hugely entertaining display of erudition. Over a single lunch, he scatters references to James Thurber, Sigmund Freud, Eudora Welty, Gustave Flaubert, W. H. Auden, and Robert Frost, among others, as readily as a precocious schoolboy rattles off the names of the states’ capitals.

He accompanies his invocation of the Oxford philosopher J. L. Austin’s theory of excuses and mitigations by leaping up and leaving the dining room. He re-emerges moments later as someone 10 minutes late for an important seminar.

As he slips back through the door, he pulls a contorted smile at the imaginary don, ceremoniously lifts his hand to conceal his mouth, then extravagantly tiptoes to his seat in the make-believe tutorial. All to make a point about the way body language and the space between words is just as important as words used.

“You see, it is an attempt to uglify yourself before someone accuses you of being stupid,” he said. “And to let it be known that you know that you have made an error before anyone else can accuse you of it. It is a pre-emption, an overt admission of guilt,” he says.

In his latest iteration of Cimarosa’s comic opera, which began as a commission by Paul Kellogg at Glimmerglass in 1992, he has continued to revise and refine the performance to magnify the meaning of the libretto. His singers are encouraged to add barely perceptible sounds — “words that do not make it into the dictionary” — to amplify the height and reinforce the quality of the comedy.

It is a hallmark of Mr. Miller’s work, not only in the 60 opera productions he has brought to life — including his record-breaking runs of “Rigoletto,” set among “Some Like It Hot” mobsters, and “The Mikado,” played as an homage to the Marx Brothers’ “Duck Soup” — but in the scores of stage plays he has directed, including a quartet of “King Lears” and a recent critically acclaimed production of “Hamlet” in Bristol, England.

He has worked to scrape the barnacles off hoary lines such as “To be or not to be” that have ossified over the centuries, losing their meaning as timeworn familiarity smothers clarity. “I told the actor playing the gravedigger that if you unearth bones in a graveyard, they are caked in earth,” he said. “The eyes of a skull will be filled with dirt. So when Hamlet takes the skull of his old friend Yorick in his hand, he does not sing, ‘Alas, poor Yorick, I knew him’; he is filled with disgust and the sudden realization that he is looking at an old friend. ‘Alas, poor Yorick!’ [Mr. Miller brushes away notional dirt and looks with concern at an imaginary skull.] ‘I knew him, Horatio.'”

This persistent habit of causing his actors and singers to deliver lines with fresh meaning, never taking anything for granted, is what makes Mr. Miller’s productions in any medium such a delight for audiences.

His method is not impulsive, nor haphazard, but rather the result of his intense, continual, and sympathetic observation of human beings going about their daily grind, backed by the intellectual theories of a string of original thinkers, such as Oxford’s J. L. Austin, Tufts’s Dan Dennett, Penn’s Erving Goffman, and Berkeley’s John Searle.

He describes the process as “attending to the overlooked.” “Half of the work of a director is sweeping the linguistic rubbish back into the text,” particularly when wringing the last drop out of comedy, he said. “The only thing you should be is to be as accurate as you can about what people really do and say. If you fill the play with those things, then people like it because they are reminded what it is like to be alive, which is the only purpose of comedy. “

He quotes the caption of a favorite New Yorker cartoon to make his point. A squirrel is on a psychiatrist’s couch, his hands joined behind his neck. He says, “But then again, like I always say, you are what you eat.” “It would not be half as funny if he had not started with the words, ‘But then again, like I always say … ‘” Mr. Miller said. “That is the sort of unnecessary accretion I mean.”

Another element is the pathos to be found in the apparently humdrum lives of ordinary people. He points to working men going about their tasks outside the Brooklyn restaurant window. One is emptying a bin of trash. Another is carrying a pole and a bucket.

“They are all what Robert Frost drew attention to in his poem ‘A Considerable Speck,'” he said. “He writes about a black speck that appears on the paper he is writing on, a speck that begins to move. He realizes that this is no mere speck but a small, almost imperceptible creature with a mind and a motive of its own. The genius of Frost is to recognize that not only are we all specks, we are all considerable specks.”

All of which will enrich “Il Matrimonio Segreto.” “You get smarter as you get older,” he said. “You see more. You see new details. I have become more and more committed to the importance of negligible details.”