知己知彼，百战不殆

Traditional form:

知己知彼，百戰不殆

Pinyin (reading):

zhījǐzhībǐ,bǎizhànbùdài

Definitions:

• know yourself and know your enemy, and you will never be defeated (idiom, from Sunzi's "The Art of War" 孫子兵法／孙子兵法 ( Sūnzǐ Bīngfǎ))

Characters:

• 知 - to know, to perceive, to comprehend
• 己 - self, oneself; personal, private; 6th heavenly stem
• 知 - to know, to perceive, to comprehend
• 彼 - that, those, the other
• 百 - one hundred; numerous, many
• 战 - war, fighting, battle
• 不 - no, not, un-; negative prefix
• 殆 - almost, probably; danger, peril; to endanger

Traditional characters:

• 知 - to know, to perceive, to comprehend
• 己 - self, oneself; personal, private; 6th heavenly stem
• 知 - to know, to perceive, to comprehend
• 彼 - that, those, the other
• 百 - one hundred; numerous, many
• 戰 - war, fighting, battle
• 不 - no, not, un-; negative prefix
• 殆 - almost, probably; danger, peril; to endanger