According to the philosopher David Hume, a miracle is "a transgression of a law of nature by a particular volition of the Deity, or by the interposition of some invisible agent". The crux of his argument is this: "No testimony is sufficient to establish a miracle, unless the testimony be of such a kind, that its falsehood would be more miraculous, than the fact which it endeavours to establish." Hume defines miracles as "a violation of the laws of nature", or more fully, "a transgression of a law of nature by a particular volition of the Deity, or by the interposition of some invisible agent." By this definition, a miracle goes against our regular experience of how the universe works. As miracles are single events, the evidence for them is always limited and we experience them rarely. On the basis of experience and evidence, the probability that miracle occurred is always less than the probability that it did not occur. As it is rational to believe what is more probable, we are not supposed to have a good reason to believe that a miracle occurred. [https://web.archive.org/web/20170320215642/http://documents.routledge-interactive.s3.amazonaws.com/9781138793934/A2/Hume/HumeMiracles.pdf]