One thing we always wondered: When Bob Dylan was growing up in the 1940s in Hibbing, Minnesota, in the home of his parents, Abe and Beatty Zimmerman, and one of his schoolmates had a birthday and there was a cake and singing, did an adult ever lean over and whisper, “Bobby, just mouth the words”?

Because for all of Dylan’s prodigious gifts, which are on mesmerizing display in Martin Scorsese’s new movie “Rolling Thunder Revue: A Bob Dylan Story,” no one ever said he was a great vocalist. Except, that is, for the millions of people who think he is. This is the Dylan paradox: It is not the notes he hits that make him great but the ones he aims for.

The Scorsese movie, which was released on Netflix, blends documentary footage of the 1975 Rolling Thunder tour with contemporary interviews with Dylan and with actors playing the latter-day bit players in the historic footage. You cannot call it fact or fiction, feature or documentary, but it has a few distinct things to say to anyone, including even to people born long afterward, about art.

Somewhere, tucked away and added to over the years, The New York Times must have a pre-filed obituary for Dylan. It could be years yet before we see it – Dylan just turned 78 in May, is still recording and touring and seems clearer than ever in the Scorsese film – but it is hard to believe he will not be worth plenty of copy far into the future. This is the man who once said “Tin Pan Alley is gone, and I put an end to it,” and largely was correct.

We can easily divide American music pre- and post-Dylan because while he was not the first popular singer-songwriter, he still changed the game, which is evident in all the artists who were dubbed “The next Dylan.” Funny thing, though: There never was a next one. And there never will be.

Dylan has also been counted out many times only to roar back, most recently in 1998 with his “Time Out of Mind” album, which may have inaugurated his most fruitful period. Has anyone ever made pop music accommodate aging and loss and Robert Burns better than Dylan did on that album’s song “Highlands”?

Sony, Dylan’s label, also just released the 14-CD set “The Rolling Thunder Revue: The 1975 live recordings.” We have only made it through five of the discs – there is only so much of this we can take in a gulp – but we would be surprised if it all was not just as immediate and fine. Take it from Eduardo Menendez, a commenter on the set’s Amazon listing, where it sells for $109.98: “This is Dylan at the very peak of the musical Mount Everest.”

The revue, a cross-country tour, was nothing new. Yet Dylan was looser surrounded by friends, and in a mime’s whiteface, his blue eyes flashing, even more intense. He sings anger with beauty, which tour mate and duet partner Joan Baez accurately says is his charisma. Everything here feels fresh, with Scarlet Rivera’s violin swirling around Dylan’s chomped-off words.

Dylan has always said he is a song and dance man, and you have to see, here, that this is his art. Art, he says at one point, is not about a state of being but of doing.

“What remains of that tour to this day?” he says now. “Nothing. Not one single thing. Ashes.”

Not by a long shot.