The impeccable John Cleese bringing comedic stylings to Heinz Hall

And now for someone completely baffling ...

An impeccable comedian who ranges from a sharp-witted egghead to a loose-limbed pratfaller, John Cleese has often been called “the funniest man alive.”

He still is — alive, that is.

Yet it hardly seems so. Once the most prolific members of the (in)famous British comedy troupe, Monty Python's Flying Circus, John Cleese has lately been about as active as a dead parrot.

Indeed, he has taken to Twitter to defend his status:

“Yes, I am still indeed alive,” he states, in his profile, “contrary to rumour.”

That is a relief to fans, even if they ponder why there isn't more of his work to enjoy.

Cleese has been involved in comedy for most of his 77 years. While studying at Cambridge University, Cleese began performing (often, with Graham Chapman) with the Footlights theatrical club. After BBC Radio and TV (“The Frost Report”) work as a writer and occasional performer, in 1969 Cleese, Chapman, Michael Palin, Terry Jones, Eric Idle and Terry Gilliam launched the irreverent, borderline dada “Monty Python's Flying Circus.” It ran for four seasons — though Cleese jumped the circus after three years. He returned for the Python film triumvirate (“The Meaning of Life,” “The Holy Grail,” “The Life of Brian”).

The master of the slow boil created and starred in the short-lived 1970s sitcom “Fawlty Towers.” In 1988, he wrote and starred in the hilarious film “A Fish Called Wanda,” then its far-less-successful sequel, “Fierce Creatures.”

Since then? Precious little for Cleesiastics, save for supporting work in Harry Potter, James Bond and other films, the odd (very) Python reunion and other occasional live shows.

One gets the nagging feeling that this comic genius has been sadly underused, after such a dynamic run in the 1970s and '80s. Then again, he arguably has been more productive — and funnier — than his fellow Pythons.

Cleese, who released a best-selling memoir “So Anyway…” in 2014, went off on a comedy tour in recent months, with his old pal Idle.

Here at Heinz Hall, he'll be solo, as part of the Pittsburgh Speakers Series.

Even without any major recent work, he remains quite a popular fellow, judging by his 5 million-plus followers on Twitter. Here, if not elsewhere, he is prolific, tweeting about politics (very liberal), tenaciously tackling trolls (“You are an (expletive) … now go boil your head”) and tossing off winking responses to admirers.

He seems open and engaging on Twitter, here answering a query as to whether his last name was originally Cheese:

“No, my father's was. He changed it when he joined the Army in 1915.”

With another tweet, he one-ups a joker:

“Another Scottish joke: Two taxis collide in Aberdeen. 35 passengers injured.”

Cleese got on his Twitter horse earlier this month, bashing British press coverage of the phone hacking scandal: “Disgusted by the organised lying about Leveson by most London newspapers today. Final proof they CANNOT be trusted to regulate themselves.”

He seems to be just as interested in American news, prominently politics. To ring in the New Year, he took on the undisputed King of Twitter:

“If Trump won't believe the briefings he gets from the CIA, the FBI and the DIA, where is he getting his new secret information from? Russia?”

And, as the anything-for-a-laugh performer does on television and in films, @JohnCleese enjoys taking comical aim at himself:

“My wife told me today that she was going to volunteer to do work in an Old Folks Home ... but then she realised she was already running one.”

Tom Scanlon is a Tribune-Review contributing writer.