PROP. IX.————
he willing to be immortalised as the advocate of mere vulgar prejudices; so that he caught adroitly at this middle term, whereby he was enabled, when reason failed him, to take shelter under popular opinion; and when popular opinion went against him, to appeal to the higher evidence of reason. Without renouncing scientific precision when it could be attained, he made friends of the mammon of unphilosophy. What chance had a writer like David Hume, with only one string to his bow, against a man who thus avowed his determination to avail himself, as occasion might require, of the plausibilities of uncritical thinking, and of the refinements of logical reflection? This amphibious method, however, had its disadvantages. At home in the submarine abysses of popular opinion, Dr Reid, in the higher regions of philosophy, was as helpless as a whale in a field of clover. He was out of his proper element. He blamed the atmosphere: the fault lay in his own lungs. Through the gills of ordinary thinking he expected to transpire the pure ether of speculation, and it nearly choked him. His fate ought to be a warning to all men, that in philosophy we cannot serve two mistresses. Our ordinary moods, our habitual opinions, our natural prejudices, are not compatible with the verdicts of our speculative reason.
19. The truth is, that Dr Reid mistook, or rather
