"'Multitudes of free thinkers,' he argued in his 'Controversies' notebook, 'deceive themselves through the ambiguous or equivocal use of the word REASON.' Their 'blunder' was in not making a proper distinction between two uses of 'reason.' 'Sometimes by the word reason,' he observed, 'is intended the same as argument or evidence... as when we say we should believe nothing without reason or contrary to reason... or against evidence.' That legitimate use of reason as an essential tool should be distinguished from making the unjustified claim that reason should be the 'highest rule,' in judging Scripture. The latter would be to speak as though 'evidence and divine revelation [were] entirely distinct, implying that divine revelation is not of the nature of evidence or argument.' It would illegitimately enthrone 'reasonable opinions' that humans arrived at on their own as necessarily higher than what they could learn from special revelation" (476, ellipses and interpolations are Marsden's).
And a further ramification of the above point:
"When Edwards [...] point[ed] out that there were many truths in electricity, magnetism, and the like that were well attested and accepted as 'reasonable' even though their first principles were not understood, he was defending history, when it is a well-attested experience, as a source of truth" (487, ellipses are mine).Marsden, Jonathan Edwards: A Life, 487