Sun Tzu on knowing your enemy
Describe who or what you are facing, or just name what is on your mind. You will get the exact passage from The Art of War that fits.
Sun Tzu's most quoted line is also his most practical: know the enemy and know yourself, and the outcome is rarely in doubt. The Art of War treats information as the real weapon, more decisive than numbers or courage. Name who or what you are facing above to find the passage that fits.
Know the enemy and yourself
His famous formula has three rungs. Know both yourself and the other side, and you are safe across a hundred contests. Know only yourself, and you will win and lose by turns. Know neither, and you will lose every time. The uncomfortable half is the second one: most people study the opponent and never honestly study themselves.
Foreknowledge wins
What lets the wise act ahead of everyone else, Sun Tzu says, is foreknowledge, and he is blunt that it cannot come from guessing or from hoping. It comes from finding things out. Stripped of the ancient setting, it is an argument for doing the homework: the person who knows the terrain in advance is rarely surprised by it.
Read the ground you are on
He likens the skilled fighter to water, which takes its shape from the land it runs over: you work out your victory in relation to the actual foe in front of you, not the one you imagined. There is no fixed playbook. The information about this situation, this opponent, this moment is what tells you what to do.
Notable lines on knowing the enemy
If you know the enemy and know yourself, you need not fear the result of a hundred battles.
Thus, what enables the wise sovereign and the good general to strike and conquer, and achieve things beyond the reach of ordinary men, is foreknowledge.
Hence it is only the enlightened ruler and the wise general who will use the highest intelligence of the army for purposes of spying and thereby they achieve great results.
Water shapes its course according to the nature of the ground over which it flows; the soldier works out his victory in relation to the foe whom he is facing.

Bring it to Sun directly
The quote is the start. Tell Sun Tzu what is actually going on and get his read on it, in a real conversation.
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