Speculative thinkers of so decidedly irreligious a temper are not numerous. If esteemed, as happens to certain commodities, in proportion to their scarcity they would enjoy a large share of public respect. Indeed, they are so few and far between, or at least so seldom make their presence visible, that William Gillespie is convinced they are an anomalous species of animal, produced by our common parent 'in a moment of madness.' Other grave Christian writers, though horrified at Atheism--though persuaded its professors, 'of all earth's madmen, most deserve a chain;' and, though constantly abusing them, are still unable to believe in the reality of such persons. These, among all the opponents of Atheism and Atheists, may fairly claim to be considered most mysterious; for, while lavishing on deniers of their Gods every kind of sharp invective and opprobrious epithet, they cannot assure themselves the 'monsters' did, or do actually exist. With characteristic humour, David Hume observed 'There are not a greater number of philosophical reasonings displayed upon any subject than those which prove the existence of Deity, and refute the fallacies of Atheists, and yet the most religious philosophers still dispute whether any man can be so blinded as to be a speculative Atheist;' 'how (continues he) shall we reconcile these contradictions? The Knight-errants who wandered about to clear the world of dragons and of giants, never entertained the least doubt with regard to the existence of these monsters.' [10:1]