What does the phrase “you can’t prove a negative” actually mean?

Question

What does the phrase “you can’t prove a negative” actually mean?

In: 1149

Answer 1

It describes information that is unfalsifiable. Good examples of this would be God, Sasquatch, and ETs. Ultimately, you can’t prove their _non-existence_, because what constitutes evidence something _doesn’t_ exist? As Donald Rumsfeld put, “the absence of evidence is not the evidence of absence.” Coincidentally, we never found evidence of WMDs in Iraq.