The social virtues must, therefore, be allowed to have a natural beauty and amiableness, which, at first, antecedent to all precept or education, recommends them to the esteem of uninstructed mankind, and engages their affections. And as the public utility of these virtues is the chief circumstance, whence they derive their merit, it follows, that the end, which they have a tendency to promote, must be some way agreeable to us, and take hold of some natural affection. It must please, either from considerations of self-interest, or from more generous motives and regards.
It has often been asserted, that, as every man has a strong connexion with society, and perceives the impossibility of his solitary subsistence, he becomes, on that account, favourable to all those habits or principles, which promote order in society, and insure to him the quiet possession of so inestimable a blessing, As much as we value our own happiness and welfare, as much must we applaud the practice of justice and humanity, by which alone the social confederacy can be maintained, and every man reap the fruits of mutual protection and assistance.
This deduction of morals from self-love, or a regard to private interest, is an obvious thought, and has not arisen wholly from the wanton sallies and sportive assaults of the sceptics. To mention no others, Polybius, one of the gravest and most judicious, as well as most moral writers of antiquity, has assigned this selfish origin to all our sentiments of virtue. [Footnote: Undutifulness to parents is disapproved of by mankind, [Greek quotation inserted here]. Ingratitude for a like reason (though he seems there to mix a more generous regard) [Greek quotation inserted here] Lib. vi cap. 4. (Ed. Gronorius.) Perhaps the historian only meant, that our sympathy and humanity was more enlivened, by our considering the similarity of our case with that of the person suffering; which is a just sentiment.] But though the solid practical sense of that author, and his aversion to all vain subtilties, render his authority on the present subject very considerable; yet is not this an affair to be decided by authority, and the voice of nature and experience seems plainly to oppose the selfish theory.