Muhammad al-Taqi (811–835) ninth of the Twelve Imams of Twelver Shi'ism
[Baqir Sharīf al-Qurashi, The life of Imam Muhammad al-Jawad, Wonderful Maxims and Arts, 2005]
Source: The Sayings and Teachings of the Great Mystics of Islam (2004), p. 28
Muhammad al-Taqi (811–835) ninth of the Twelve Imams of Twelver Shi'ism
[Baqir Sharīf al-Qurashi, The life of Imam Muhammad al-Jawad, Wonderful Maxims and Arts, 2005]
Sun Tzu (-543–-495 BC) ancient Chinese military general, strategist and philosopher from the Zhou Dynasty
Variant translations
If you know others and know yourself, you will not be imperiled in a hundred battles; if you do not know others but know yourself, you win one and lose one; if you do not know others and do not know yourself, you will be imperiled in every single battle.
Know your enemy and know yourself, find naught in fear for 100 battles. Know yourself but not your enemy, find level of loss and victory. Know not thy enemy nor yourself, wallow in defeat every time.
Literal translation: Know [the] other, know [the] self, hundred battles without danger; not knowing [the] other but know [the] self, one win one loss; not knowing [the] other, not knowing [the] self, every battle must [be] lost.
Source: The Art of War, Chapter III · Strategic Attack
“If you have an enemy, then learn and know your enemy, don't just be mad at him or her”
Denzel Washington (1954) actor, screenwriter, director, producer
“What's worse…?
The devil you don't know… or the devil you do?”
Jodi Picoult book Keeping Faith
Source: Keeping Faith
“To know your Enemy, you must become your Enemy.”
Sun Tzu (-543–-495 BC) ancient Chinese military general, strategist and philosopher from the Zhou Dynasty
This is sometimes attributed to Sun Tzu in combination with the above quote, as well as alone, but it too has not been sourced to any published translation of The Art of War, though it is similar in concept to his famous statement in Ch. 3 : "It is said that if you know your enemies and know yourself, you will not be imperiled in a hundred battles..."
Misattributed
Orson Scott Card book Pastwatch: The Redemption of Christopher Columbus
Pastwatch: The Redemption of Christopher Columbus (1996)
Malcolm X (1925–1965) American human rights activist
Advice to the Youth of Mississippi (31 December 1964) http://www.britannica.com/blackhistory/article-9399834 <br class="br">Variant: You get freedom by letting your enemy know that you'll do anything to get your freedom; then you'll get it. It's the only way you'll get it. <br class="br">Context: You get freedom by letting your enemy know that you'll do anything to get your freedom; then you'll get it. It's the only way you'll get it.