paradox

"A statement that seems contradictory or absurd but is actually valid or true. According to one proverbial paradox, we must sometimes be cruel in order to be kind. Another form of paradox is a statement that truly is contradictory and yet follows logically from other statements that do not seem open to objection. If someone says, “I am lying,” for example, and we assume that his statement is true, it must be false. The paradox is that the statement “I am lying” is false if it is true."

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