It has been 45 years since Chicago first recorded the two-part song “Dialogue” for the album Chicago V.

Written by founding member Robert Lamm, the song reflected a countryman’s indifference to war and social turmoil.

Lyrically a conversation takes place between a college student protected by campus life (performed by former vocalist and bass player Peter Cetera) and another concerned youth who acknowledges the world’s problems (sung by the late and legendary guitarist Terry Kath).

It was a period of time that saw many protests against U.S. involvement in the Vietnam War and outbursts of civil unrest.

Lamm said the song and its message are still relevant today.

In a phone interview with The Blade, prior to the band’s appearance at Centennial Terrace at 8 p.m. today, the songwriter and composer said if it were written today “it wouldn’t change at all, unfortunately.”

There are still “people who are left out of the process and people who have too much power. It really hasn’t changed very much,” he said pointing to the decades-long war in the Middle East.

Lamm didn’t hint at if it would be on the band’s playlist for tonight’s show. The Heart and Soul Tour 3.0 is co-headlined by Earth, Wind & Fire.

He did say that many of Chicago’s hits and instantaneously recognizable songs, from the heart-pumping “25 or 6 to 4” to heart-wrenching ballads like “If You Leave Me Now,” will be played.

All together, Chicago is scheduled to perform at least 30 songs from a vast discography that spans six decades and generated countless awards and accolades. The latest was induction into the Rock and Roll Hall of Fame in April.

Lamm, who is as talented on vocals and organs as he is a lyricist, will be joined by the horns and woodwind section including founding members Lee Loughnane and James Pankow, as well as Ray Hermann; Jeff Coffey on bass and vocals; Tris Imboden on drums; Keith Howland on guitar and vocals; Lou Pardini on keyboards and vocals; and Walfredo Reyes, Jr., on percussion.

The performance will start with tunes off the band’s first album, Chicago Transit Authority, which featured “Does Anybody Really Know What Time it Is.” A top 10 hit, it was also written by Lamm.

As a lyricist, Lamm is “happy to explain them where I can.”

Like anyone who puts effort and skill into his craft, he has “improved over time,” and his lyrical expressions aim to be original and imaginative.

“What I’ve worked on is trying to communicate my ideas and my emotions in an interesting way lyrically, or a way that’s unique. And sometimes I can go kind a little off the deep end. Even my wife says, ‘Why do you write those complicated lyrics?’

“It’s really about a challenge to myself. I don’t want to repeat myself. I don’t want to work in clichés. I want to write something that is clear, or is clear to me anyway, but sometimes that needs to be explained, and I’m happy to do that when I’m asked,” he said.

Listening to some of Chicago’s songs, one may think the words were written effortlessly, but much labor went into crafting lyrics that sound that way.

He recalled an article written on a website about songwriting where the author explained what elements were needed for a great composition, and he used a song from Chicago’s latest album as an example.

“[The author’s] point was that guys who have been writing songs for a long time — Bruce Springsteen, Paul Simon, to name a few — although the song might sound accidental and kind of tossed and casual, but those of us who’ve been working our whole lives as composers, none of that is accidental. It’s all really thought out,” he said.

Many times he has explained “25 or 6 to 4,” which is simply “a song about writing.” That song is a testament to why the band, formed in 1967 in Chicago, has been praised for an original sound, one that blended brassy horns and jazz with rock and roll.

Lamm wrote the arrangement, including the horns, and thankfully for listeners, left a place for Kath’s groundbreaking, brilliant guitar solo. Kath, who died in 1978, composed music by ear only and was praised by Jimi Hendrix.

“Kath was just an amazing guitarist. That solo actually is, it’s one of those solos that kids who are learning to play rock guitar eventually aspire to play — note for note if they can,” he said.

Despite the accolades and trailblazing songs written over the decades, this band, like many, has not been without controversy. Most recently was Cetera’s absence at the Rock Hall induction. A prolific lyricist, he left Chicago in ’85 to launch his solo career.

“The only way he wanted to be there is if he brought his band. ... which is not Chicago,” Lamm said.

Lamm said he would occasionally speak to Cetera before, and the group was excited to play with the original members at the April induction; however, after recent events he said, “I think that, it will be a while before I speak to him again.”

Before the event, Cetera posted to his website a suggestion to play “25 or 6 to 4” in “the key of E.”

Lamm explained that the Rock Hall has a planned-out program where it determines who is going to play, in what order, which songs.

He added that changing the key to that song was complicated; it has been done in the past with much rehearsing.

“‘25 or 6 to 4’ is complicated, and you just can’t walk out run it down one time and have it,” he said.

Contact Natalie Trusso Cafarello at: 419-724-6133, or ntrusso@theblade.com, or on Twitter @natalietrusso.

First Published August 28, 2016, 4:00 a.m.