Therefore I Am" is a song by American singer Billie Eilish. The song was written by Eilish and her brother Finneas O'Connell, with production being handled by the latter.
It was released as the second single of her second studio album, Happier Than Ever, by Darkroom and Interscope Records on November 12, 2020. It is an uptempo, hip hop-influenced pop, dark pop, R&B, and electropop track.
The song received positive reviews from music critics, with many of them comparing it to Eilish's hit single "Bad Guy". "Therefore I Am" was featured in 2020 year-end lists by multiple publications, including Billboard, NME, and Uproxx. The song peaked at number two on the US Billboard Hot 100, giving Eilish her fourth top-10 hit in the United States. The song further reached the top five on the Billboard airplay Hot Rock & Alternative Songs and Mainstream Top 40 charts. It peaked at number one on the singles charts in Greece, Ireland, Lithuania, and New Zealand, alongside receiving a platinum certification in Canada from Music Canada (MC).
The song's music video, directed by Eilish herself and filmed inside the Glendale Galleria shopping mall in California, premiered on the same day as the single release. In the video, Eilish is by herself in the empty shopping mall, eating and drinking various foods and beverages from Wetzel's Pretzels, Hot Dog on a Stick, and Chipotle Mexican Grill. Eilish performed the song at American Music Awards of 2020 in November 2020.