Elvis Costello is in a philosophical mood on this sombre, wet, late fall afternoon.

Spectacle: Elvis Costello with . . . Bono & The Edge, the next instalment in Costello's open-ended series of conversations about music, with the people who make music, premieres on Canadian TV on Dec. 11.

Another six conversations will air early in the new year, featuring Bruce Springsteen, Sheryl Crow, Lyle Lovett and Ron Sexsmith, among others. It's an eclectic guest list, but Costello, whose personal musical style and deeply textured lyrics have made him one of his generation's most innovative and influential songwriters, says there's no thought or design behind it.

Costello doesn't think of Spectacle in terms of seasons, just as he doesn't think of his on-air conversations as straight question-and-answer sessions. Spectacle's 13 episodes that have already aired were part of a piece, he suggests. Costello doesn't regard the seven episodes to come as a second season, but rather as another part of the piece.

Asked if he sees Spectacle living beyond the next part of the piece, Costello at first gives a guarded answer about tight finances and the economic crunch facing network television, then segues into a more candid and heartfelt answer about how he doesn't dwell on the future, but rather, focuses on the present.

Costello regards Spectacle's 20 hours -- last season's 13 episodes and the seven episodes to come -- as a self-contained work, a visual symphony in roughly two dozen movements. In Costello's eyes, Spectacle is already a complete work. He views it as an artistic expression more than a TV show. And, like all artistic expressions, there are no set rules about when to stop and when to keep going. Costello will know in his heart when the time has come to compose Spectacle's final coda.

"When I'm hosting a show, I always think, 'This could be the last one I do,' because I usually go into everything I do as if it's the last," Costello says. "I think that approach keeps you on your mettle."

Costello is still jazzed, though, by the idea of sitting down with the greats -- and the not-so-greats -- and sharing thoughts on musical styles and influences. He regards Spectacle as two shots of happy and one shot of sad, and he touches off each conversation with a self-referential poetry slam, set to music.

Away from the plush couch and bright lights of Toronto's Masonic Temple, Costello talks about the art of conversation. It's not something he finds easy to articulate at first -- he's more used to shaping Spectacle's conversation than being on the receiving end -- but, over time, he warms to his subject.

"I feel more surprise than pride," Costello says, reflecting on Spectacle's early days. "To be honest, I haven't looked at many of the shows, but I remember there were moments when I was genuinely surprised by what came out. I was glad I put in the time to figure things out about people's careers, about some of their less well-known songs, and it got a remarkable response. There's so much to talk about, that it's a tremendous responsibility. I was glad that I asked those questions, because things came up that probably would not have come up in any other context."

If Costello allows himself any pride, it was in the diverse range of musical styles and genres as represented by a first-year guest list that ranged from Lou Reed, James Taylor, Smokey Robinson, Rufus Wainwright and Tony Bennett to less pop/rock-oriented guests, such as opera soprano Renee Fleming, jazz legend Herbie Hancock and former U.S. president Bill Clinton.

Costello says he wishes, in hindsight and partly in jest, that he had handled the Spectacle conversation with his wife, virtuoso jazz pianist Diana Krall, but his Spectacle co-producer Elton John drew out a side of Krall that Costello wouldn't have.

John quipped at the time that he had never interviewed anyone on television before, then engaged Krall in some revealing piano talk about her influences, from Fats Waller, Joni Mitchell and Bill Evans to her favourite, Nat King Cole.

The on-stage performances are a key reason that Spectacle works, Costello reasons, and on that night, Krall performed a stirring rendition of Cole's Exactly Like You, backed by bassist Christian McBride and drummer Karriem Riggins.

Spectacle was never intended to resemble one of the late-night talk shows, which Costello describes as "a different form of entertainment" that's staged and paced primarily for comedic effect.

The traditional late-night talk shows are filmed in real time -- "very little is edited out" -- whereas Spectacle is paced more like a free-flowing conversation, so Costello and his guest-of-the-moment have the time to hit the right notes. Each hour of Spectacle takes three or four hours to film, Costello estimates.

Costello doesn't actively think of names or seek guests for Spectacle.

"One of the problems with having a beautiful set is that the show is not that mobile."

The guest list is more an in-the-moment decision: who happens to be available, and who engages Costello's interest at the time. That artist can be just as much a young ingenue, finding her voice, as it can be a music legend.

"I don't feel any compulsion, as a rule," Costello says. "I just want to have a good show. And I find the best shows are collaborative shows; they're complementary with one another."

In perhaps his most disarming admission, Costello reveals he wanted Taylor Swift to appear on Spectacle, but the Kanye West incident at the MTV Video Music Awards happened the very same weekend Spectacle's producers approached Swift. Swift hesitated, then declined. Costello suspects the sudden, dramatic fallout from the MTV Awards controversy, coupled with the sudden, white-hot glare of the media spotlight, caused Swift to have cold feet. By the time Swift was ready to reconsider, both she and Costello had moved on to other projects.

Costello feels a conversation with the exceedingly young, yet not untalented, Swift would have made an important addition to the Spectacle canon. Swift represents the flip side of Spectacle's more familiar lineup of Hall of Fame inductees and legendary rockers. Swift is a fast-rising star on the cusp of a potentially long and meaningful music career.

"I think she is quite interesting, and I thought it would be very snobbish to not try to get someone like that. You can see a degree of self-possession there, and I'm intrigued by that. She's a very young girl whom you don't want to judge based on what people are writing down about her, saying, `Well, that's just such-and-such.' How do you know? It's like saying to a teenager in love, 'Oh, it's not real; just get on with it.' Well, it's very real when you're in love and you're a teenager.

"It's the same with pop. There are very few songs about young people that are written from a teenager's perspective. When you see her sing, you can see that coming alive inside her, in the moment. When she's singing, it means exactly what it says it means."

Spectacle: Elvis Costello with . . . Bono & The Edge airs Friday on CTV starting Friday, Dec. 11 at 10 ET/PT.