Who said "This above all: to thine own self be true."?

This quote is attributed to William Shakespeare.

This above all: to thine own self be true. - William Shakespeare

"This above all: to thine own self be true."

William Shakespeare

Playwright Poet English 1564–1616

"To be, or not to be, that is the question"

"All the world's a stage, and all the men and women merely players"

"Some are born great, some achieve greatness, and some have greatness thrust upon them"

"The course of true love never did run smooth"