criterion proposed by the philosopher of science Karl Popper as a solution to the demarcation problem
if statement can be falsified, then it is scientific if not, then it is not scientific
A theory or hypothesis is falsifiable (or refutable) if it can be logically contradicted by an empirical test.
Popper argued that science should try to falsify theories rather than confirm them, because no amount of observations can prove a theory true, but one observation can prove it false
he argued that verifiability is not a sufficient criterion, because many non-scientific statements, such as metaphysical or religious claims, can also be verified by some observations.
He also pointed out that verification can never be conclusive, because there may always be some exceptions or alternative explanations that are not yet observed
Popper argued that science should try to falsify theories rather than confirm them, because no amount of observations can prove a theory true, but one observation can prove it false