These principles, duly developed, are the true basis of morals; nothing is more chimerical than those which are founded upon imaginary motives placed out of nature; or upon innate sentiments; which some speculators have regarded as anterior to man's experience; as wholly independant of those advantages which result to him from its use: it is the essence of man to love himself; to tend to his own conservation; to seek to render his existence happy: thus interest, or the desire of happiness, is the only real motive of all his actions; this interest depends upon his natural organization, rests itself upon his wants, is bottomed upon his acquired ideas, springs from the habits he has contracted: he is without doubt in error, when either a vitiated organization or false opinions shew him his welfare in objects either useless or injurious to himself, as well as to others; he marches steadily in the paths of virtue when true ideas have made him rest his happiness on a conduct useful to his species; in that which is approved by others; which renders him an interesting object to his associates. _Morals_ would be a vain science if it did not incontestibly prove to man that _his interest consists in being virtuous._ Obligation of whatever kind, can only be founded upon the probability or the certitude of either obtaining a good or avoiding an evil. Indeed, in no one instant of his duration, can a sensible, an intelligent being, either lose sight of his own preservation or forget his own welfare; he owes happiness to himself; but experience quickly proves to him, that bereaved of assistance, quite alone, left entirely to himself, he cannot procure all those objects which are requisite to his felicity: he lives with sensible, with intelligent beings, occupied like himself with their own peculiar happiness; but capable of assisting him, in obtaining those objects he most desires; he discovers that these beings will not be favorable to his views, but when they find their interest involved; from which he concludes, that his own happiness demands, that his own wants render it necessary he should conduct himself at all times in a manner suitable to conciliate the attachment, to obtain the approbation, to elicit the esteem, to secure the assistance of those beings who are most capacitated to further his designs. He perceives, that it is man who is most necessary to the welfare of man: that to induce him to join in his interests, he ought to make him find real advantages in recording his projects: but to procure real advantages to the beings of the human species, is to have virtue; the reasonable man, therefore, is obliged to feel that it is his interest to be virtuous. _Virtue is only the art of rendering himself happy, by the felicity of others_. The virtuous man is he who communicates happiness to those beings who are capable of rendering his own condition happy; who are necessary to his conservation; who have the