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Every man has a price which he will willingly accept. Even for that which he never wanted to sell.
— Lord Cutler Beckett · Pirates of the Caribbean: Dead Man's Chest

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
The speaker holds a cynical view of human nature: everyone can be bought, and the price may be one they would accept willingly. This includes even what they swore never to give up. Principles, in this claim, are only things not yet offered enough for.
Context reviewed