Who said "From one thing, know ten thousand."?

Miyamoto Musashi (c. 1584–1645). Source: The Book of Five Rings, Earth (The Five Scrolls).

What is the original Japanese?

一を以て萬を知る事、兵法の利也. Translated from the original Japanese by Spartan Surfers.

From one thing, know ten thousand.

Miyamoto Musashi, The Book of Five Rings, Earth (The Five Scrolls)

The source

"From one thing, know ten thousand." Miyamoto Musashi said it in The Book of Five Rings, Earth (The Five Scrolls). Translated from the original Japanese by Spartan Surfers.

"一を以て萬を知る事、兵法の利也"

Original Japanese, The Book of Five Rings, Earth (The Five Scrolls). Japanese: Miyamoto Musashi (Kinkodo, 1909), NDL digital text.

Who said it

Miyamoto Musashi (c. 1584–1645). Undefeated swordsman who wrote The Book of Five Rings in a cave a few weeks before he died.

Questions

Who said "From one thing, know ten thousand."?: Miyamoto Musashi (c. 1584–1645). Source: The Book of Five Rings, Earth (The Five Scrolls).
What is the original Japanese?: 一を以て萬を知る事、兵法の利也. Translated from the original Japanese by Spartan Surfers.