What is it when someone says the opposite of what he or she really means?

Answer 1

Depending on the context, tone of voice/writing used, and strength of belief in the opposing truth, there can be a variety of answers.

Sarcasm: This is generally a lighter tone and will be generally understood quickly to intend the opposite of the words spoken. I.e. "Yeah, she'll be home for dinner." if said in a sarcastic tone would easily be inferred to mean that she will not make dinner.

Irony: Similar to sarcasm, but this typically underlies a more emotional or treasured belief. I.e. "I love how people are only valued as dollar signs." if said ironically would be inferred to mean that you believe strongly that people are worth more than their economic values.

Hypocrisy: This is when somebody makes a statement that unwittingly contradicts a belief that they hold. Unlike sarcasm, this is not intentional, but accidental. I.e. If a slave-owner said, "I believe that all people should be free." he would be speaking hypocritically because he is actually taking part in the act of enslaving other humans.

Argumentum ad Absurdum: "Arguing to the Absurd" is a technique used commonly to prove a point that a person does not like is wrong because it leads to some absurd consequence that its advocator cannot condone. The arguer does not typically believe the absurd case either. I.e. Arguer 1 says, "I believe all workers should make a wage." Arguer 2 (absurd case) replies, "Well, doesn't that mean that children should pay their mothers for their work?"

Denial: The person could know the truth, but consciously reject it because that truth would disappoint or anger the person. I.e. A girl may say "My boyfriend still loves me" when what she really means to say is "Comfort me since my boyfriend dumped me and I don't know how to handle it."