Who said "Knowing others is smart. Knowing yourself is clear."?

Lao Tzu (6th century BC). Source: Tao Te Ching 33.

Knowing others is smart. Knowing yourself is clear.

Lao Tzu, Tao Te Ching 33

The source

"Knowing others is smart. Knowing yourself is clear." Lao Tzu said it in Tao Te Ching 33. Translated from the original Chinese by Spartan Surfers.

"知人者智，自知者明。"

Original Chinese, Tao Te Ching 33. Chinese: Wang Bi edition via zh.wikisource.

Who said it

Lao Tzu (6th century BC). Keeper of the archives at the Zhou court, by tradition the author of the Tao Te Ching: eighty-one short chapters on water, softness and knowing when to stop.

Questions

Who said "Knowing others is smart. Knowing yourself is clear."?: Lao Tzu (6th century BC). Source: Tao Te Ching 33.
What is the original Chinese?: 知人者智，自知者明。. Translated from the original Chinese by Spartan Surfers.