The most mysterious and mystifying of all numbers!
It is the number of cabalistic power (Hebrew), the trinity of trinities (Christian), the number of perfection (Greek), and the superlative of superlatives (Sanskrit).
There are 9 heavens, 9 orders of angels, 9 planets, 9 Muses, 9 crosses, 9 worthies, 9 crowns of heraldry, 9 lives of a cat, 9 months of pregnancy, 9 days of mortification, 9 days of wonder, 9 regions of hell, 9 heads of the hydra, modern leases for 99 years, ancient leases for 999 years, and the cat-o'-nine tails suggests perfect punishment and atonement.
There are 9 openings to the body, 9 major cuts of pig meat, 9 basic components and 9 directories in Figurski at Findhorn on Acid, 9 themes in the Notes directory, 9 nodes in which openings are mentioned, 9 Frequently Asked Questions about Ralph the Swimming Pig, and 9 Rorschach inkblots from tests refused by Frank Figurski. There are even precisely 9 words in this sentence.
— Extrapolated from Robert L. Ripley, Ripley's Big Book: Believe It or Not! (Simon and Schuster, 1934)