"Human Nature" was written by Steve Porcaro of Toto and John Bettis for Michael Jackson's Thriller album. Initially, Porcaro recorded a rough demo of the song on a cassette.[1] Fellow Toto band member David Paich then gave the demo, along with two songs written by Paich, to producer Quincy Jones, hoping they would be included on Thriller.[1] Jones didn't like Paich's songs, but enjoyed the rough demo of "Human Nature" at the end of the cassette.[1] Jones explained, "All of a sudden, at the end, there was all this silence, there was: 'why, why, dah dah da-dum dah dah, why, why'. Just a dummy lyric and a very skeletal thing—I get goosebumps talking about it. I said, 'This is where we wanna go, because it's got such a wonderful flavour'".[2] The producer asked if the song could be included on Jackson's album, to which Porcaro and Bettis agreed.[1] "Human Nature" was the last song selected for Thriller, ousting "Carousel" from the final track listing.[1]