The phrase 'the reaction to The Decline and Fall calls immediately and perhaps exclusively to mind the hostile response the first volume of Gibbon's history provoked among the pious; so successfully has the uproar from the orthodox drowned quieter, but equally revealing reactions. One such reaction comes from Hume. In his Memoirs, Gibbon quotes his letter of congratulation on the publication of Volume I, in which his fellow historian writes suggestively of the volume's concluding chapters:

When I heard of your undertaking (which was some time ago) I own, that I was a little curious to see how you would extricate yourself from the subject of your two last chapters. I think you have observed a very prudent temperament: but it was impossible to treat the subject so as not to give grounds of suspicion against you, and you may expect that a clamour will arise.

It is the second sentence which, in its precision of response, is the more arresting. The recognition of Gibbon's prudence in his handling of Christianity, and the simultaneous prediction of the controversy which would arise, show Hume the practitioner's awareness of how Gibbon's irony is a weapon both sharp and, as far as possible, safe.