Robert's Father: At last, you know what it means to hate. Now you're ready to be a king.
Robert the Bruce: My hate will die with you.
William Wallace: I will invade England and defeat the English on their own ground!
Argyle Wallace: First, learn to use this. [Taps young William on the forehead.] Then, I'll teach you to use this. [Holds up his sword.]
Longshanks: I shall offer a truce and buy him off. But, who will go to him? Not I. If I fell under the sword of that murderer, it might be my head in a basket. And not my gentle son. The mere sight of him would only encourage an enemy to take over the whole country.
William: They may take our lives, but they'll never take our freedom!
William Wallace: Sons of Scotland, I am William Wallace.
William: Before we let you leave, your commander must cross that field, present himself before this army, put his head between his legs, and kiss his own ass.
William Wallace: Are you ready for a war?
William Wallace: I came back home to raise crops, and God willing, a family. If I can live in peace, I will.
Chosen answer: Just like he said, it would dull his wits and not leave him fully lucid the next day when he had to face the torture.
LorgSkyegon
He wanted his full awareness so he didn't accidentally yell for mercy.