Etymology Journal · I

If you say so

Meaning

A passive-aggressive way of signaling that you do not believe what the other person just said, but you are choosing not to argue about it.

Skeptical, dismissive

He told me he finished the report on time, and I just replied if you say so.
She insisted the party would be fun despite the lack of music, so I just said if you say so.
If you say so, but I have a hard time believing that engine is actually fine.

This is a standard English idiom that relies entirely on tone. It has been used to politely dismiss opinions for as long as people have been arguing.

Nationwide

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