 Kames did not dedicate an entire book to an attack on Hume on religion, but George Campbell (1719–1796) did. This interesting man, a student at Marischal College, Aberdeen, of which in 1759 he became Principal, was a founder-member of the Aberdeen Philosophical Society, the ‘Wise Cub’, which also included Thomas Reid, John Gregory, David Skene, Alexander Gerard, James Beattie and James Dunbar. It is probable that many of Campbell’s writings began life as papers to the Club. In 1763 he published A Dissertation on Miracles which was intended as a demolition of Hume’s essay ‘On miracles’, Chapter Ten in An Enquiry Concerning Human Understanding. Miracles were commonly discussed in eighteenth century Scotland. On the one hand the Kirk required people to accept miracle claims on the basis either of eyewitness reports or of reports of such reports, and on the other hand the spirit of Enlightenment required that claims based on the authority of others be put before the tribunal of reason. Hume focuses especially on the credibility of testimony, and argues that the credence we place in testimony is based entirely on experience, the experience of the occasions when testimony has turned out to be true as against those experiences where it has not. Likewise it is on the basis of experience that we judge whether a reported event occurred. If the reported event is improbable we ask how probable it is that the eyewitness is speaking truly. We have to balance the probability that the eyewitness is speaking truly against the improbability of the occurrence of the event. Hume held that the improbability of a miracle is always so great that no testimony could tell effectively in its favour. The wise man, proportioning his belief to the evidence, would believe that the testimony in favour of the miracle is false.