The calendar may have caught up with the man who 43 years ago ruminated in song on the strangeness of finding himself 70, but Paul Simon isn’t slowing down.

At an age at which most performers are content to rest on their laurels, or in Simon’s case his considerable publishing royalties, the Rock and Roll Hall of Famer still pursues the pace of a young singer-songwriter looking to build a legacy.

Simon is touring in support of this year’s Hear Music/Concord Records release “So Beautiful or So What,” with the 24-date fall leg of his U.S. trek arriving Oct. 19 at the Gibson Amphitheatre in L.A.

On Oct. 24, Columbia Legacy, now the home of Simon’s entire back catalog, will issue a compilation, “Songwriter.” The two-CD, 32-track set is a retrospective with a difference: a Simon-curated selection focusing on his cleffing.

In the wings is a 25th-anni documentary on Simon’s bestselling 1986 opus “Graceland” — one of two Simon solo albums to win Grammy’s album of the year, set to bow on A&E early next year.

Simon notes that “So Beautiful or So What,” which bowed at No. 4 on the U.S. album chart in April and has sold 250,000 to date, was something of a return to form after years of rhythmic experimentation — the African and Afro-Brazilian sounds of “Graceland” and “Rhythm of the Saints” (1990), the doo-wop and Latin music of “Songs From the Capeman” (1997), the understated world music eclecticism of “You’re the One” (2000) and the sonically adventurous Brian Eno collaboration “Surprise” (2006).

“I purposely didn’t want to start with a rhythmic premise,” Simon says. “I wanted to go and write the way I used to write years ago, with just a guitar. I’d been doing the other for 20-some-odd years, and I knew how to do it, and was used to it. I wanted to break out of that particular style and go back to other things that I do. I knew it was going to be uncomfortable and difficult to sit in the room just by myself, which was a good reason to do that. I just wanted to be uncomfortable.”

The result is a bracing, frequently wry song cycle, co-produced by Simon and longtime collaborator Phil Ramone. The album features offbeat instrumentation (ranging from African kora to New Orleans jazz clarinet) and samples (from preacher Rev. J.M. Gates, gospel’s Golden Gate Jubilee Quartet and bluesman Sonny Terry). Many of the musing compositions are distinctly spiritual in nature; on three tracks — “The Afterlife,” “Love and Hard Times” and “Love Is Eternal Sacred Light” — God is a central character

“It just happened,” Simon says. “There’s been a lot of speculation, especially in Christian blogs and writing, that God was speaking through me, and I was unaware. Certainly I’m not a Christian. I’m not actually a religious person at all. But (it’s) in a lot of my songs, and has been throughout the years.”

Simon’s highly personal look back at his song catalog on “Songwriter” largely eschews his writing for Simon & Garfunkel: Live solo performances of “The Sound of Silence” and “The Boxer” and, somewhat surprisingly, Aretha Franklin’s 1971 recording of “Bridge Over Troubled Water” — rather than the original, famous for Garfunkel’s soaring vocal — represent his work for the duo.

“It’s a songwriter album,” Simon says. “I wanted to get in as many of these (solo) album tracks that deserved to get in as I could, so I cut Simon & Garfunkel back quite a bit — probably more than in all fairness (those songs) deserved. Again, because I wanted to keep the emphasis on the song, I chose the Aretha, which I think is just as good as the Simon & the Garfunkel (version) … I thought it was extraordinary.”

Some of Simon’s major hits — “Me and Julio Down by the Schoolyard,” “Loves Me Like a Rock,” “50 Ways to Leave Your Lover,” “Slip Slidin’ Away” — fell by the wayside on “Songwriter” in favor of lesser-known compositions.

“I was trying to combine songs that were well-known with songs that I thought were really interesting but essentially overlooked, or others that were kind of semi-hits,” Simon says. “?’Hearts and Bones’ was a semi-hit; fans of mine would all know that. ‘Peace Like a River’ is a semi-hit; indie bands covered it. Other songs like ‘Tenderness’ or ‘Rene and Georgette Magritte With Their Dog After the War,’ some of the songs from ‘Surprise,’ they’re really not known.

” ‘Darling Lorraine’ (from ‘You’re the One’) was another song that I thought, when I wrote it, was one of the best songs I wrote. I thought that song was a leap for me as a songwriter. … The story evolved as I was writing it. I didn’t even know that she died until (the narrator) said, ‘I’m sick to death of you, Lorraine.’ As soon as I wrote that, I said, ‘Oh, my God, she’s gonna die now.’ It was a very good story-song about a relationship. It had a lot of jokes in it, too, which I like.”

The “Graceland” doc, helmed by Joe Berlinger, director of the “Paradise Lost” documentaries about the West Memphis Three murder case, focuses on a defining moment in Simon’s career — the controversial genesis of the album in South Africa during the waning years of apartheid. The album was made despite a U.N. boycott against South Africa, and wound up broadening the worldwide appreciation of the many forms of black South African music.

“We went back to South Africa at the end of July,” says Simon. “I had a little brief reunion concert with all of the guys. Everyone’s alive except for (singer) Miriam (Makeba). We played in front of an audience, with very little rehearsal. Everybody was interviewed. They interviewed a lot of people from the (African National Congress), people who were opposed to us in the beginning. We also went to the musicians who played, and Roy Halee, who was the engineer. We all talked about where it came from and how people see it now. It’s really the artistic story of ‘Graceland’ and the political story of ‘Graceland,’ 25 years later.”

Simon says there’s talk of a “Graceland” reunion tour in 2012. “I’ll start to bring a little bit more ‘Graceland’ back (into my set), and get (it) into shape.”

Reflecting on his current state of creative hyperactivity, Simon demurs when it is suggested — as annotator Tom Moon does on “Songwriter” — that he is a restless individual.

I’m a curious person,” he says. “I’m interested. It’s not restlessness that grabs me. It’s something that’s interesting. … I’m going backwards in time, and I’m going forwards in time, because I’m rethinking structure all the time, because I’ve been writing songs for so long that I’m good at it.”