We've found 3 phrases for assertion (0.116 seconds):

been there, done that »    An assertion that the speaker has personal experience or knowledge of a particular place or topic and is now bored.

do the math »    You can do the calculation yourself, with the implication that you don't have to trust someone else's assertions.

surprise surprise »    An indication that the unsurprising happened, especially contrary to someone's hopes or assertions.

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