ideas, and by their juxta-position and comparison. In order, therefore, to judge of these systems, we need only consider, whether it be possible, from reason alone, to distinguish betwixt moral good and evil, or whether there must concur some other principles to enable us to make that distinction. If morality had naturally no influence on human passions and actions, ’twere in vain to take such pains to inculcate it; and nothing wou’d be more fruitless than that multitude of rules and precepts, with