Bruce Springsteen says: "The first time I heard Bob Dylan... it was like somebody had kicked open the doors of my mind." Me, too. And millions more.
It is easy to remember, but hard to explain how Dylan arrived in an instant to irradiate imaginations. Here in sequence are his first seven singles: Corrina, Corrina, Blowin' in the Wind, The Times They Are a-Changing, Maggie's Farm, Subterranean Homesick Blues, Like a Rolling Stone and Positively 4th Street.
If he'd never written another word, he'd still be remembered forever with awe.
He has had his bad moments, too. The last time I saw him, sitting a mile away in an arena with all the soul of a cement factory, I hadn't worked out by the end of the set which of the badly-lit guys on stage was the main man. Couldn't tell one song from another, either, so mumbled were the lyrics and mangled the melodies.
On the other hand, my partner, Goretti, once wangled the two of us into a semi-private Dylan gig at a small club in Dublin where I am convinced we held steady eye-contact as he bantered and sang through a sumptuous selection from Another Side of Bob Dylan, Bringing It All Back Home, Highway 61 Revisited and so forth. You should have been there.
The political highpoint came when Dylan immediately preceded Martin Luther King's "I have a dream" speech at the Lincoln Memorial in Washington in August 1963, with Only a Pawn in the Game, about the murder in Mississippi two months earlier of civil rights organiser Medgar Evers.
Watch on YouTube now and see with what grace the 21-year-old Jewish guy from Minnesota absorbs the close on a million mainly black faces before him as he sings with aching empathy not about a victim of racism, or a hero of anti-racist struggle, but about the killer who'd had hatred put into his heart.
'A South politician preaches to the poor white man/You got more than blacks, don't complain/You're better than them, you been born with white skin they explain/And the Negro's name/Is used it is plain/For the politician's gain/As he rises to fame/And the poor white remains/On the caboose of the train/But it ain't him to blame/He's only a pawn in their game.'
The conventional wisdom has it that Dylan soon figured out the old order wasn't fading fast, or at all, so he abandoned rebellion, went wayward and electric, offered his services to them who bargained money for forgiveness, became a song-and-dance man for the crass bourgeoisie.
He indulged sinful political thoughts he knew would dismay his old comrades: 'And if my thought-dreams could be seen/They'd probably put my head in a guillotine/But it's alright, Ma, it's life, and life only.'
There were still powerful political songs to come - George Jackson in 1971, about the prison death of the Soledad Brother, or Hurricane from 1975, an epic account of the wrongful murder conviction of middleweight contender Reuben Carter. But the question whether Dylan sold out is misconceived. It's to imply that he ever bought in.
His consistency over 50 years has lain precisely in constant adaptation to the changing material conditions, cultural assumptions and political mores around him.
He has always been rooted in the ever-shifting moment.
Incontrovertibly, he has recently written some rubbish: 'You may be an ambassador to England or France/You may like to gamble, you might like to dance/You may be the heavyweight champion of the world/You may be a socialite with a long string of pearls/But you're gonna have to serve somebody, yes indeed.' Oh, dear.
In the end, his transcendent achievement has been to write songs of authentic personal feeling which also evoke the transfiguration of the world once cleansed of oppression:
'Far between sundown's finish and midnight's broken toll/We ducked inside a doorway, thunder went crashing/As majestic bells of bolts struck shadows in the sound/Seeming to be the chimes of freedom flashing... Tolling for the aching whose wounds cannot be nursed/For the countless confused, accused, misused, the strung-out ones and worse/And for every hung-up person in the whole wide universe/We gazed upon the chimes of freedom flashing.'
He's still making concentric circuits of the world, still tripping on the magic swirling ship, still keeping ahead of the reach of crazy sorrow.
And him 70.