Hume's Maxim
- That no testimony is sufficient to establish a miracle, unless the testimony be of such a kind, that its falsehood would be more miraculous that the fact which it endeavors to establish
Note: This quote is taken from Why People Believe Weird Things by Michael Shermer.
Hume's Maxim is a method of evaluating a claim (a miracle) based on some given evidence (testimony). When presented with evidence for some claim, and the evidence cannot be directly validated, consider which possibility is more likely, that the claim and evidence is true, or that the evidence itself is false. The more likely possibility should be believed.
As an example, imagine that someone comes to you and claims to have seen a ghost. One cannot immediately verify the evidence (that the individual did see a ghost) so should you believe the claim? Applying Hume's Maxim one must consider the two possibilities, first the claim is true and the person did indeed see a ghost or the evidence is false (the person is either lying or believes they saw a ghost, but did not). Which ever option seems more likely should be believed.
It is important to note that Hume's Maxim is not a method of proof. Just because Hume's Maxim implies that one option is more likely, it does not mean that option is actually the correct one. However when presented with incomplete and potentially false evidence, Hume's Maxim can be used as a tool for evaluating a claim.