Popper’s Falsifiability Principle:
For a theory to be considered scientific,
it must be falsifiable.
Thought:
Even the scientific are called theories
as they might be invalidated in time,
by other theories that seem more valid later,
in the quest for truth.
(In philosophy, a razor is a principle or rule of thumb that allows one to eliminate (‘shave off’) unlikely explanations for a phenomenon, or avoid unnecessary actions.)