彼を知り己を知れば、百戦して殆うからず。彼を知らずして己を知れば、一勝一負す。彼を知らず己を知らざれば、戦うごとに必ず殆うし。 - 孫武 (紀元前544頃? - 前496頃?): 『孫子（兵法）』謀攻篇
/ (［（漢）知彼知己者、百戦不殆。不知彼而知己、一勝一負。不知彼不知己、毎戦必殆。］)
/ 敵を知ると同時に自分自身を知れ。
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If you know the enemy and know yourself, you need not fear the result of a hundred battles. If you know yourself but not the enemy, for every victory gained you will also suffer a defeat. If you know neither the enemy nor yourself, you will succumb in every battle. - Sun Tzu [Sun Zi] (c.544? - c.496?B.C.): The Art of War "Attack by Stratagem" (trans. by Lionel Giles (1875 - 1958))
/ Know yourself as well as your enemy.
![IMAGE: The usefulness of (the) useless. [Everyone knows the usefulness of useful things, but no one knows the usefulness of useless things. / Everyone knows the use of the useful, but not the use of the useless.] (Even if something did not bring immediate benefit, it could still turn out to be valuable.)](https://www.ok312.net/wp-content/uploads/2026/01/place-name-sign-822236_640-100x71.jpg)
![IMAGE: Patriotism is your conviction that this country is superior to all others because you were born in it. [Patriotism: Your conviction that this country is superior to all other countries because you were born in it. / Patriotism is, fundamentally, a conviction that a particular country is the best in the world because you were born in it.]](https://www.ok312.net/wp-content/uploads/2025/10/ai-generated-9017144_640-100x67.jpg)
![IMAGE: The wheel is come full circle. / The wheel has come [turned] full circle.](https://www.ok312.net/wp-content/uploads/2014/06/wagon-wheel-204998_640-100x66.jpg)
![IMAGE: Treasure every encounter, for it will never recur. [Once-in-a-lifetime encounter.] / Opportunity knocks but once. [Opportunity knocks only once.] / Opportunity seldom knocks twice.](https://www.ok312.net/wp-content/uploads/2015/10/tea-680540_640-100x67.jpg)
![IMAGE: The highest branch is not the safest roost. / Envy is the companion of honor [honour].](https://www.ok312.net/wp-content/uploads/2018/10/tree-603013_640-100x75.jpg)