against indigo

1. no one has ever pointed at the sky and said "indigo." they say blue, or they say purple. the word lives on a poster in a third-grade classroom and nowhere else.
2. newton needed seven colors because seven was a holy number. he had six. he wedged in indigo and called it observation. the rainbow was tampered with for numerology and we never undid it.
3. blue and violet are already adjacent on the wheel. asking for a sliver between them is asking the wheel to grow a tooth.
4. nobody owns an indigo shirt. they own dark blue shirts they later describe as indigo when complimented. the compliment is what the color is for.
5. "indigo bunting" is blue. "indigo girls" are folk. "indigo dye" is so blue it bleeds blue. the noun does not match its modifiers and we keep it anyway out of habit.
6. every other color in the rainbow is a primary or a clean mix of two primaries. indigo is a mix of a mix. it's already a derivative when it arrives.
7. a six-color rainbow is a better rainbow. it has the moral authority of sufficiency. seven is a marketing decision.
8. removing indigo costs nothing. no painting changes. no flag changes. no song needs a new lyric. the only loss is the mnemonic, and "ROY G. BV" sounds like a dependable mid-level employee, which is more than the current arrangement can claim.