It was Lee Hays, of the Weavers, who once said the 11th commandment ought to be “Never give up a grudge.” Hays has something in common with Benny Silverman, the pivotal character in Jeffrey Sweet’s drama “The Value of Names.”

Like so many other artists, Hays and the fictitious Silverman, an actor, were both blacklisted in the ’50s after they were named as Communists before the House Un-American Activities Committee.

“The Value of Names,” set some three decades later, in 1981 (coincidentally the year Lee Hays died), kicks into high gear when Benny (Thomas Mahard), who eventually made it big in a TV sitcom, again encounters the onetime friend who had denounced him before Congress, film director Leo Greshen (Phil Powers). A play of conflicting viewpoints and philosophies, “Names” is also and always a play with a beating heart – three, actually: Benny’s, Leo’s and that of Leo’s daughter, Norma (Kathryn Mahard, Thom Mahard’s daughter).

Yolanda Fleischer’s production at the Jewish Ensemble Theatre never lets the play’s intellectuality stray from its humanity. Early on, Benny and Norma discuss whether Norma, an up-and-coming actress, should keep the part she’s been offered in a play; its original director has dropped out and been replaced by Benny’s old nemesis. Father and daughter speak in ideas fit for a college ethics class – as a TV star, Benny refused to work with people whose politics he disdained; doesn’t that make him guilty of blacklisting? – but their mutual affection is evident. For instance, Benny, who has taken up painting in retirement, gives his daughter’s nose a playful flick with a paintbrush.

Leo shows up on Benny’s Malibu patio, ostensibly to persuade Norma to stay in the play Leo is directing. Norma, knowing there’s more at stake, eventually leaves and lets the two old adversaries have their long-avoided meeting.

Amid the cerebral give-and-take, with talk of Communist dogma, right-wing bigotry, of Trotsky, Stalin, Nixon, Ezra Pound, and the value of holding on versus moving on, it’s clear that each man is more than the sum of his thoughts. And Fleischer ensures that the play is more than a static discussion. As Mahard moves around the stage, watering a profusion of greenery, he is a man who won’t be pinned down. Powers, in need of not quite forgiveness but something similar, is the one who literally and figuratively reaches out.

Thomas Mahard is nicely wry and righteous as the wronged Benny, and Kathryn Mahard is convincing as the one who’s always in the middle, between the two men, between Benny and his ex-wife (talked about but never seen), but the real wonder here is Powers who seems to have disappeared into his character. He looks different, his voice is different. It’s not just, there’s Phil Powers doing a good job playing so-and-so; it’s where did Phil Powers go?

What’s come to be known as McCarthyism, even when it predates the late senator, has been well chronicled in film and on stage – very notably in Arthur Miller’s allegorical “The Crucible,” about a literal witch-hunt – but rarely so clearly and concisely as in “The Value of Names.”