Graham Nash remains cautiously optimistic about the chance for another reunion of Crosby Stills Nash and Young, despite the recent falling out between David Crosby and Neil Young.

It all started when Crosby sharply criticized Young for dating actress Daryl Hannah in the aftermath of Young's split with wife Pegi. Crosby deemed Hannah "a purely poisonous predator"; Young countered by saying he'd never work with CSNY again.

"You know, whatever Neil wants to say is fine with me," Nash counters, in a new talk with SiriusXM. "It would be sad to me if the music of Crosby Stills Nash and Young didn’t go forward because of an inappropriate statement by David to Neil about his relationship with Daryl Hannah. I mean if we’re not more grown up and if we’re not more realistic about what the true value of our friendship is, it would be very sad to me.”

Crosby Stills Nash and Young rose to the top of the album charts in 1970 with 'Deja Vu,' as their debut spun off a trio of Top 40 singles. They quickly scattered, however, for solo projects -- trying, but failing, to reunite several times. 'American Dream' finally emerged in 1988, then another decade passed before CSNY issued a third album, 'Looking Forward.'

They haven't toured as a quartet since 2006, though Crosby Stills and Nash continue working together in various configurations. Still, Nash reminds, that shared history provides a foundation that this particular disagreement shouldn't break.

"I mean you’ve got to understand, Neil Young knows what we bring to his music," Nash says. "He’s not a fool. He’s just a little upset right now. And I understand it. You know, he’s going through personal problems with his wife, Pegi. They’re getting divorced. You know, he’s found true love that he says with Daryl Hannah perhaps. And the ways of the heart are mysterious and I can only wish both Pegi and Neil and Daryl the very, very best with their life. Let’s get on with it and let’s see what happens."