put up or shut up
verb1
Idiomatic To desist from saying something unless one is able to prove it; to act in a manner that makes further talk unnecessary.
- "If the evidence for modern Darwinian theory is so overwhelming, they should have called the bluff on the other side and come and made their arguments. ... They should have put up or shut up."2005 June 21, Cornelia Dean, “Opting Out in the Debate on Evolution”, in The New York Times, archived from the original on 11 Feb 2021, retrieved 22 Jun 2011:
- Related terms
- put one's money where one's mouth is, fish or cut bait