The Meaning Behind “I Should Have Known It,” Tom Petty and the Heartbreakers’ Tribute to the Ultimate Guitar God and the Ultimate Rock Guitar

Sometimes an instrument can inspire a song. On Mojo, Tom Petty and the Heartbreakers wrote an entire album because of a single guitar.

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Eight years had passed between Heartbreakers albums, and it was time to get the band back together. The hiatus was split in 2006 by Petty’s third and final solo album, Highway Companion. “Saving Grace,” from Companion, was a bluesy stomp featuring Mike Campbell and Jeff Lynne. Campbell said Petty was listening to the blues in the gap after the Heartbreakers’ previous album, The Last DJ, so it wasn’t surprising where the band landed on Mojo

Campbell had purchased the holy grail of electric guitars—a 1959 Gibson Les Paul sunburst. The ’59 Les Paul is a rare guitar that costs as much as a house. Only 500 or 600 were made by Gibson, and though limited, the guitar changed rock ‘n’ roll history. 

An Ode to the Most Famous Devotee of the Most Famous Electric Guitar

On Led Zeppelin I, Jimmy Page played a Fender Telecaster. The glorious guitar sound that opens “Good Times Bad Times” is a Telecaster raging through a small tube amplifier. A dirty little secret of guitar players is that the best way to achieve a mammoth guitar sound in the studio is by recording through a small tube amp.

But Page needed something more while performing live with Led Zeppelin. He was the only guitarist on stage and wanted a guitar with a bigger sound. Chasing the sound of early Fleetwood Mac’s Peter Green, he found what he was looking for in a 1959 Gibson Les Paul. What came to be known as the classic Jimmy Page sound is, in reality, a Peter Green sound. 

There are other ways to achieve a heavy blues sound. Jack White sounded like Thor with pawnshop guitars in Detroit. But this particular heavy blues sound requires a Les Paul.

Traditionally, Campbell achieved his jangly Heartbreakers sound using Fender and Rickenbacker guitars. The Les Paul was a dramatic change, and Petty was intrigued. With his blues obsession and Campbell’s new guitar, Petty wanted to make an album around the Les Paul. Thus, the sound of Mojo was born, and the loudest example of the new/old sound is on the album’s single, “I Should Have Known It.”

[RELATED: 5 Impactful Moments in Tom Petty’s Career That Solidified His Legacy\ 

Babe, I’m Gonna Leave You

“I Should Have Known It” is a classic Petty grievance song—somebody’s done him wrong, and he’s had enough. 

Well I shoulda known it
I shoulda seen
Leave it to you
To treat me mean
Every promise was just a runaround
I shoulda known it
Yeah, you’re gonna let me down
Well, it’s over now, you see
It’s the last time you’re gonna hurt me

Petty spits rage over British-inspired blues. During the blues revival of the 1960s, the U.K. bands acted like a mirror for American roots music. White kids from another country discovered an American treasure and brought it to the mainstream. Playing a Led Zeppelin-inspired riff, the Heartbreakers reflected heavy blues back across the pond. 

Cross-pollination of cultures was one of Tom Petty’s best moves. He became iconic by blending Southern rock with the jangly sounds of California dream pop. Petty’s trusty travel companion was Campbell, a vital guitar player deserving the same respect as Jimmy Page, Keith Richards, or George Harrison. 

Sold down the river
Left for dead
Yeah, you’re puttin’ ideas
In another man’s head
And it’s over now, you see
It’s the last time you’re gonna hurt me

Writing a brilliant, simple song is incredibly complex and challenging. Petty’s genius was taking the things you’ve already heard and making them sound like new poetry. He wrote from the heart and gut, using plain language, the patois of blues and rock ‘n’ roll, and delivered the message like Dylan’s subsumed prophet. 

Get Back

Returning to Campbell’s guitar and the reason Mojo exists, old instruments carry the stories of ghosts. It doesn’t matter whether you believe Robert Johnson made a pact with the devil; the myth of rock ‘n’ roll is just another version of searching for something more significant than the individual. It’s a communal experience where Bruce Springsteen once sang about the audience “speaking in tongues.” 

The ghost in the guitar is the unwritten song or riff—the unfinished business left behind by the previous owner. The creative process is a combination of art and craft. The craft provides the necessary tools to be ready when inspiration comes knocking around. Campbell’s riff profoundly moved Petty, but it wasn’t different from the way the guitar spoke to Campbell in the first place.

The interconnectedness between humans shows up in the uncontrollable way the body moves to the sound of a ’59 Les Paul in the hands of someone like Mike Campbell. Crank up “I Should Have Known It,” really crank it, and dare your body not to move. 

Photo by Ethan Miller/Getty Images