I am sensible, that nothing can be more unphilosophical than to be positive or dogmatical on any subject; and that, even if excessive scepticism could be maintained, it would not be more destructive to all just reasoning and inquiry. I am convinced that, where men are the most sure and arrogant, they are commonly the most mistaken, and have there given reins to passion, without that proper deliberation and suspense, which can alone secure them from the grossest absurdities. Yet, I must confess, that this enumeration puts the matter in so strong a light, that I cannot, at PRESENT, be more assured of any truth, which I learn from reasoning and argument, than that personal merit consists entirely in the usefulness or agreeableness of qualities to the person himself possessed of them, or to others, who have any intercourse with him. But when I reflect that, though the bulk and figure of the earth have been measured and delineated, though the motions of the tides have been accounted for, the order and economy of the heavenly bodies subjected to their proper laws, and Infinite itself reduced to calculation; yet men still dispute concerning the foundation of their moral duties. When I reflect on this, I say, I fall back into diffidence and scepticism, and suspect that an hypothesis, so obvious, had it been a true one, would, long ere now, have been received by the unanimous suffrage and consent of mankind. PART II. Having explained the moral APPROBATION attending merit or virtue, there remains nothing but briefly to consider our interested OBLIGATION to it, and to inquire whether every man, who has any regard to his own happiness and welfare, will not best find his account in the practice of every moral duty. If this can be clearly ascertained from the foregoing theory, we shall have the satisfaction to reflect, that we have advanced principles, which not only, it is hoped, will stand the test of reasoning and inquiry, but may contribute to the amendment of men's lives, and their improvement in morality and social virtue. And though the philosophical truth of any proposition by no means depends on its tendency to promote the interests of society; yet a man has but a bad grace, who delivers a theory, however true, which, he must confess, leads to a practice dangerous and pernicious. Why rake into those corners of nature which spread a nuisance all around? Why dig up the pestilence from the pit in which it is buried? The ingenuity of your researches may be admired, but your systems will be detested; and mankind will agree, if they cannot refute them, to sink them, at least, in eternal silence and oblivion. Truths which are pernicious to society, if any such there be, will yield to errors which are salutary and ADVANTAGEOUS.