Sometimes the moment calls for simplicity. Sometimes it calls for the theory of relativity.

"Head Down" is not a fairy tale, a cartoonish parable, or pithy aphorism. It's not even nice.

"Head Down" is a tour de force, to me the single greatest song Soundgarden ever produced, the crown jewel of an entire album that will stand for complex greatness for as long as there are people who care to remember the past.

This has to be the heaviest song ever that prominently features an acoustic guitar. It layers well with with a gang of electric guitars, all in an arcane tuning. The modality and rhythm of the central guitar theme is a nod to lead guitarist Kim Thayil's Indian heritage and the influence of Indian classical music, known for its melodic and rhythmic complexity.

The drumming is one of Matt Cameron's definitive performances, a showpiece of rudimentary skill that is simultaneously tabla and jazz-informed heavy rock. His cymbal in the verses crashes with ideal tone and sustain.

I also have to praise the bass playing of Ben Shepard who plays key, mobile parts in the instrumental sections.

Like many songs I'm fascinated by, this one has no choruses. There are scintillating instrumental sections led by the guitar theme; there are looming verses; there is a savage middle development that rings out into a kind of shared lead and rhythm guitar solo; there is a psychedelic outtro fading into the foundational soil of those drums, which only quit of their own volition.