Thomas Fuller

Thomas Fuller (1608 – 16 August 1661) was an English churchman and historian. He is now remembered for his writings, particularly his Worthies of England, published after his death. He was a prolific author, and one of the first English writers able to live by his pen. His widely acknowledged sense of humour kept him from extremes. “By his particular temper and management,” said Laurence Echard in his History of England, “he weathered the late great storm with more success than many other great men.”

First get an absolute conquest over thyself.

Further Reading:
Alexander Pope on Know Thyself
Richard of Saint Victor on Know Thyself
Anonymous English Monk on Know Thyself