The sessions for the Thriller album were like a musical Apollo program, but instead of sending humans to the moon, Michael Jackson was trying to send music into the collective consciousness of the global human species. Even in the 1980s, when there was a relatively narrow series of channels that entertainment could reach the masses, that was proving to be a Promethean task.
Over the course of the '60s and '70s, people had already burrowed themselves into micro-identities based on entertainment genres. A person into disco music didn't necessarily find an interest in hard rock. A fan of soul music maybe wasn't up on the trends of New Wave pop. By the 1980s, the idea that everyone could collectively enjoy a single artist was already seeming like a lost ideal.
Michael Jackson grew up as an entertainer in this world of fracturing audiences, and for some reason, he took it upon himself to create the maximum crossover music. His first experiment in unlocking uber-music was the 1979 album Off the Wall. From what I've read, sessions for the album were maniacally detail oriented, putting every best effort forward in every aspect of the songs. And while a classic, its sales still stalled far below the level of a true collective event. While very fun, it's still at its core just a disco album. His scope was still too shallow.
For the Thriller sessions, Michael Jackson got philosophical, sociological, even scientific about the "songness" of his songs.
The music couldn't simply be good; it had to be calibrated to activate the deepest musical receptors in the human brain. The album's DNA had to feature the most appealing traits shared in all of the most established genres.
"Wanna Be Startin' Somethin'" is the opening mission statement of the album, and it says everything about why Thriller was the generational, international crossover musical achievement that it was.
What is "Wanna Be Startin' Something'"? Disco? Pop? Funk? World beat? The brass section sounds like a Latin big band. There's a rock-styled electric guitar solo in there too. It's all the compass points and none, and a trajectory to the stars.