If the man who consults his reason has real and powerful motives for doing good to others and abstaining from injuring them, he has present motives equally urgent to restrain him from the commission of vice. Experience may suffice to show him that if he becomes sooner or later the victim of his excesses, he ceases to be the friend of virtue, and exists only to serve vice, which will infallibly punish him. This being allowed, prudence, or the desire of preserving one's self free from the contamination of evil, ought to inculcate to every man his path of duty; and, unless blinded by his passions, he must perceive how much moderation in his pleasures, temperance, chastity, contribute to happiness; that those who transgress in these respects are necessarily the victims of ill health, and too often pass a life both infirm and unfortunate, which terminates soon in death.
How is it possible, then, Madam, from visionary theories to arrive at these conclusions, and establish from supernatural phantasms the principles of private and public virtue? Shall we launch into unknown regions to ascertain our duty and to keep our station in society? Is it not sufficient if we wish to be happy that we should endeavor to preserve ourselves in those maxims which reason approves, and on which virtue is founded? Every man who would perish, who would render his existence miserable, whoever would sacrifice permanent happiness for present pleasure, is a fool, who reflects not on the interests that are dearest to him.
If there are any principles so clear as the morality of humanity has been and is still proved to be, they are such as men ought to observe. They are not obscure notions, mysticism, contradictions, which have made of a science the most obvious and best demonstrated, an unintelligible science, mysterious and uncertain to those for whom it is designed. In the hands of the priests, morality has become an enigma; they have founded our duties on the attributes of a Deity whom the mind of man cannot comprehend, in place of founding them on the character of man himself. They have thrown in among them the foundations of an edifice which is made for this earth. They have desired to regulate our manners agreeably to equivocal oracles which every instant contradict themselves, and which too often render their devotees useless to society and to themselves. They have pretended to render their morality more sacred by inviting us to look for recompenses and punishments removed beyond this life, but which they announce in the name of the Divinity. In fine, they have made man a being who may not even strive at perfection, by a preordination of some to bliss, and consequent damnation of others, whose insensibility is the result of this selection.
Need we not, then, wonder that this supernatural morality should be so contrary to the nature and the mind of man? It is in vain that it aims at the annihilation of human nature, which is so much stronger, so much more powerful, than imagination. In despite of all the subtile and marvellous speculations of the priests, man continues always to love himself, to desire his well being, and to flee misfortune and sorrow. He has then always been actuated by the same passions. When these passions have been moderate, and have tended to the public good, they are legitimate, and we approve those actions which are their effects. When these passions have been disordered, hurtful to society, or to the individual, he condemns them; they punish him; he is dissatisfied with his conduct which others cannot approve. Man always loves his pleasures, because in their enjoyment he fulfils the end of his existence; if he exceeds their just bounds he renders himself miserable.
The morality of the clergy, on the other hand, appears calculated to keep nature always at variance with herself, for it is almost always without effect even on the priesthood. Their chimeras serve but to torture weak minds, and to set the passions at war with nature and their dogmas. When this morality professes to restrain the wicked, to curb the passions of men, it operates in opposition to the established laws of natural religion; for by preserving all its rigor, it becomes impracticable; and it meets with real devotees only in some few fanatics who have renounced nature, and who would be singular, even if their oddities were injurious to society. This morality, adopted for the most part by devotees, without eradicating their habits or their natural defects, keeps them always in a state of opposition even with themselves. Their life is a round of faults and of scruples, of sins and remorse, of crimes and expiations, of pleasures which they enjoy, but for which they again reproach themselves for having tasted. In a word, the morality of superstition necessarily carries with it into the heart and the family of its devotees inward distress and affliction; it makes of enthusiasts and fanatics scrupulous devotees; it makes a great many insensible and miserable; it renders none perfect, few good; and those only tolerable whom nature, education, and habit had moulded for happiness.
It is our temperament which decides our condition; the acquisition of moderate passions, of honest habits, sensible opinions, laudable examples, and practical virtues, is a difficult task, but not impossible when undertaken with reason for one's guide, It is difficult to be virtuous and happy with a temperament so ardent as to sway the passions to its will. One must in calmness consult reason as to nis duty. Nature, in giving us lively passions and a susceptible imagination, has made us capable of suffering the instant we transgress her bounds. She then renders us necessary to ourselves, and we cannot proceed to consult our real interest if we continue in indulgence that she forbids. The passions which reason cannot restrain are not to be bridled by religion. It is in vain that we hope to derive succors from religion if we despise and refuse what nature offers us. Religion leaves men just such as nature and habit have made them; and if it produce any changes on some few, I believe I have proved that those changes are not always for the better.
Congratulate yourself, then, Madam, on being born with good dispositions, of having received such honest principles, which shall carry you through life in the practice of virtue, and in the love of a fine and exalted taste for the rational pleasures of our nature. Continue to be the happiness of your family, which esteems and honors you. Continue to diffuse around you the blessings you enjoy; continue to perform only those actions which are esteemed by all the world, and all men will respect you. Respect yourself, and others will respect you. These are the legitimate sentiments of virtue and of happiness. Labor for your own happiness, and you will promote that of your family, who will love you in proportion to the good you do it. Allow me to congratulate myself if, in all I have said, I have in any measure swept from your mind those clouds of fanaticism which obscure the reason; and to felicitate you on your having escaped from vague theories of imagination. Abjure superstition, which is calculated only to make you miserable; let the morality of humanity be your uniform religion; that your happiness may be constant, let reason be your guide; that virtue may be the idol of your soul, cultivate and love only what is virtuous and good in the world; and if there be a God who is interested in the happiness of his creatures, if there be a God full of justice and goodness, he will not be angry with you for having consulted your reason; if there be another life, your happiness in it cannot be doubtful, if God rewards every one according to the good done here.
I am, with respect, &c.