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• The Spirit of Laws.
• Book XX.: Of Laws In Relation to Commerce, Considered In Its Nature and Distinctions.
• Chap. I.: Of Commerce.
• Chap. II.: Of the Spirit of Commerce.
• Chap. III.: Of the Poverty of the People.
• Chap. IV.: Of Commerce In Different Governments.
• Chap. V.: Of Nations That Have Entered Into an œconomical Commerce.
• Chap. VI.: Some Effects of an Extensive Navigation.
• Chap. VII.: The Spirit of England, With Respect to Commerce.
• Chap. VIII.: In What Manner the œconomical Commerce Has Been Sometimes Restrained.
• Chap. IX.: Of the Prohibition of Commerce.
• Chap. X.: An Institution Adapted to œconomical Commerce.
• Chap. XI.: The Same Subject Continued.
• Chap. XII.: Of the Freedom of Commerce.
• Chap. XIII.: What It Is That Destroys This Liberty.
• Chap. XIV.: The Laws of Commerce Concerning the Confiscation of Merchandises.
• Chap. XV.: Of Seizing the Persons of Merchants.
• Chap. XVI.: An Excellent Law.
• Chap. XVII.: A Law of Rhodes.
• Chap. XVIII.: Of the Judges of Commerce.
• Chap. XIX.: That a Prince Ought Not to Engage Himself In Commerce.
• Chap. XX.: The Same Subject Continued.
• Chap. XXI.: Of the Commerce of the Nobility In a Monarchy.
• Chap. XXII.: A Singular Reflection.
• Chap. XXIII.: To What Nations Commerce Is Prejudicial.
• Book XXI.: Of Laws Relative to Commerce, Considered In the Revolutions It Has Met With In the World.
• Chap. I.: Some General Considerations.
• Chap. II.: Of the People of Africa.
• Chap. III.: That the Wants of the People In the South Are Different From Those of the North.
• Chap. IV.: The Principal Difference Between the Commerce of the Ancients and the Moderns.
• Chap. V.: Other Differences.
• Chap. VI.: Of the Commerce of the Ancients.
• Chap. VII.: Of the Commerce of the Greeks.
• Chap. VIII.: Of Alexander. His Conquest.
• Chap. IX.: Of the Commerce of the Grecian Kings After the Death of Alexander.
• Chap. X.: Of the Circuit of Africa.
• Chap. XI.: Of Carthage and Marseilles.
• Chap. XII.: The Isle of Delos. Mithridates.
• Chap. XIII.: Of the Genius of the Romans As to Maritime Affairs.
• Chap. XIV.: Of the Genius of the Romans With Respect to Commerce.
• Chap. XV.: Of the Commerce of the Romans With the Barbarians.
• Chap. XVI.: Of the Commerce of the Romans With Arabia, and the Indies.
• Chap. XVII.: Of Commerce After the Destruction of the Western Empire.
• Chap. XVIII.: A Particular Regulation.
• Chap. XIX.: Of Commerce After the Decay of the Roman Power In the East.
• Chap. XX.: How Commerce Broke Through the Barbarism of Europe.
• Chap. XXI.: The Discovery of Two New Worlds, and In What Manner Europe Is Affected By It.
• Chap. XXII.: Of the Riches Which Spain Drew From America.
• Chap. XXIII.: A Problem.
• Book XXII.: Of Laws In Relation to the Use of Money.
• Chap. I.: The Reason of the Use of Money.
• Chap. II.: Of the Nature of Money.
• Chap. III.: Of Ideal Money.
• Chap. IV.: Of the Quantity of Gold and Silver.
• Chap. V.: The Same Subject Continued.
• Chap. VI.: The Reason Why Interest Was Lowered One Half After the Conquest of the Indies.
• Chap. VII.: How the Price of Things Is Fixed In the Variation of the Sign of Riches.
• Chap. VIII.: The Same Subject Continued.
• Chap. IX.: Of the Relative Scarcity of Gold and Silver.
• Chap. X.: Of Exchange.
• Chap. XI.: Of the Proceedings of the Romans With Respect to Money.
• Chap. XII.: The Circumstances In Which the Romans Changed the Value of Their Specie.
• Chap. XIII.: Proceedings With Respect to Money In the Time of the Emperors.
• Chap. XIV.: How the Exchange Is a Constraint On Despotic Power.
• Chap. XV.: The Practice of Some Countries In Italy
• Chap. XVI.: The Assistance a State May Derive From Bankers.
• Chap. XVII.: Of Public Debts.
• Chap. XVIII.: Of the Payment of Public Debts.
• Chap. XIX.: Of Lending Upon Interest.
• Chap. XX.: Of Maritime Usury.
• Chap. XXI.: Of Lending By Contract, and the State of Usury Amongst the Romans.
• Chap. XXII.: The Same Subject Continued.
• Book XXIII.: Of Laws In the Relation They Bear to the Number of Inhabitants.
• Chap. I.: Of Men and Animals, With Respect to Multiplication of Their Species.
• Chap. II.: Of Marriage.
• Chap. III.: Of the Condition of Children.
• Chap. IV.: Of Families.
• Chap. V.: Of the Several Orders of Lawful Wives.
• Chap. VI.: Of Bastards In Different Governments.
• Chap. VII.: Of the Father’s Consent to Marriage.
• Chap. VIII.: The Same Subject Continued.
• Chap. IX.: Of Young Women.
• Chap. X.: What It Is That Determines to Marriage.
• Chap. XI.: Of the Severity of Government.
• Chap. XII.: Of the Number of Males and Females In Different Countries.
• Chap. XIII.: Of Sea-port Towns.
• Chap. XIV.: Of the Productions of the Earth Which Require a Greater Or Less Number of Men.
• Chap. XV.: Of the Number of Inhabitants With Relation to the Arts.
• Chap. XVI.: The Concern of the Legislator In the Propagation of the Species.
• Chap. XVII.: Of Greece, and the Number of Its Inhabitants.
• Chap. XVIII.: Of the State and Number of People Before the Romans.
• Chap. XIX.: Of the Depopulation of the Globe.
• Chap. XX.: That the Romans Were Under a Necessity of Making Laws, to Encourage the Propagation of the Species.
• Chap. XXI.: Of the Laws of the Romans Relating to the Propagation of the Species.
• Chap. XXII.: Of the Exposing of Children.
• Chap. XXIII.: Of the State of the World After the Destruction of the Romans.
• Chap. XXIV.: The Changes Which Happened In Europe, With Regard to the Number of the Inhabitants.
• Chap. XXV.: The Same Subject Continued.
• Chap. XXVI.: Consequences.
• Chap. XXVII.: Of the Law Made In France to Encourage the Propagation of the Species.
• Chap. XXVIII.: By What Means We May Remedy a Depopulation.
• Chap. XXIX.: Of Hospitals.
• Book XXIV.: Of Laws As Relative to Religion, Considered In Itself, and In Its Doctrines.
• Chap. I.: Of Religion In General.
• Chap. II.: A Paradox of Mr. Bayle’s.
• Chap. III.: That a Moderate Government Is Most Agreeable to the Christian Religion, and a Despotic Government to the Mahometan.
• Chap. IV.: Consequences From the Character of the Christian Religion, and That of the Mahometan.
• Chap. V.: That the Catholic Religion Is Most Agreeable to a Monarchy, and the Protestant to a Republic.
• Chap. VI.: Another of Mr. Bayle’s Paradoxes.
• Chap. VII.: Of the Laws of Perfection In Religion.
• Chap. VIII.: Of the Connection Between the Moral Laws and Those of Religion.
• Chap. IX.: Of the Essenes.
• Chap. X.: Of the Sect of Stoics.
• Chap. XI.: Of Contemplation.
• Chap. XII.: Of Penances.
• Chap. XIII.: Of Inexpiable Crimes.
• Chap. XIV.: In What Manner Religion Has an Influence On Civil Laws.
• Chap. XV.: How False Religious Are Sometimes Corrected By the Civil Laws.
• Chap. XVI.: How the Laws of Religion Correct the Inconveniencies of a Political Constitution.
• Chap. XVII.: The Same Subject Continued.
• Chap. XVIII.: How the Laws of Religion Have the Effect of Civil Laws.
• Chap. XIX.: That It Is Not So Much the Truth Or Falsity of a Doctrine Which Renders It Useful Or Pernicious to Men In Civil Government, As the Use Or Abuse of It.
• Chap. XX.: The Same Subject Continued.
• Chap. XXI.: Of the Metempsychosis.
• Chap. XXII.: That It Is Dangerous For Religion to Inspire an Aversion For Things In Themselves Indifferent.
• Chap. XXIII.: Of Festivals.
• Chap. XXIV.: Of the Local Laws of Religion.
• Chap. XXV.: The Inconveniency of Transplanting a Religion From One Country to Another.
• Chap. XXVI.: The Same Subject Continued.
• Book XXV.: Of Laws As Relative to the Establishment of Religion and Its External Polity.
• Chap. I.: Of Religious Sentiments.
• Chap. II.: Of the Motives of Attachment to Different Religions.
• Chap. III.: Of Temples.
• Chap. IV.: Of the Ministers of Religion.
• Chap. V.: Of the Bounds Which the Laws Ought to Prescribe to the Riches of the Clergy.
• Chap. VI.: Of Monasteries.
• Chap. VII.: Of the Luxury of Superstition.
• Chap. VIII.: Of the Pontificate.
• Chap. IX.: Of Toleration In Point of Religion.
• Chap. X.: The Same Subject Continued.
• Chap. XI.: Of Changing a Religion.
• Chap. XII.: Of Penal Laws.
• Chap. XIII.: A Most Humble Remonstrance to the Inquisitors of Spain and Portugal.
• Chap. XIV.: Why the Christian Religion Is So Odious In Japan.
• Chap. XV.: Of the Propagation of Religion.
• Book XXVI.: Of Laws, As Relative to the Order of Things On Which They Determine.
• Chap. I.: Idea of This Book.
• Chap II.: Of Laws Divine and Human.
• Chap. III.: Of Civil Laws Contrary to the Law of Nature.
• Chap. IV.: The Same Subject Continued.
• Chap. V.: Cases In Which We May Judge By the Principles of the Civil Law, In Limiting the Principles of the Law of Nature.
• Chap. VI.: That the Order of Succession Or Inheritance Depends On the Principles of Political Or Civil Law, and Not On Those of the Law of Nature.
• Chap. VII.: That We Ought Not to Decide By the Precepts of Religion, What Belongs Only to the Law of Nature.
• Chap. VIII.: That We Ought Not to Regulate By the Principles of the Canon Law, Things Which Should Be Regulated By Those of the Civil Law.
• Chap. IX.: That Things Which Ought to Be Regulated By the Principles of Civil Law, Can Seldom Be Regulated By Those of Religion.
• Chap. X.: In What Case We Ought to Follow the Civil Law Which Permits, and Not the Law of Religion Which Forbids.
• Chap. XI.: That Human Courts of Justice Should Not Be Regulated By the Maxims of Those Tribunals Which Relate to the Other Life.
• Chap. XII.: The Same Subject Continued.
• Chap. XIII.: In What Cases, With Regard to Marriage, We Ought to Follow the Laws of Religion; and In What Cases We Should Follow the Civil Laws.
• Chap. XIV.: In What Instances Marriages Between Relations Should Be Regulated By the Laws of Nature; and In What Instances By the Civil Laws.
• Chap. XV.: That We Should Not Regulate By the Principles of Political Law, Those Things Which Depend On the Principles of Civil Law.
• Chap. XVI.: That We Ought Not to Decide By the Rules of the Civil Law, When It Is Proper to Decide By Those of the Political Law.
• Chap. XVII.: The Same Subject Continued.
• Chap. XVIII.: That It Is Necessary to Enquire, Whether the Laws Which Seem Contradictory, Are of the Same Class.
• Chap. XIX.: That We Should Not Decide Those Things By the Civil Law, Which Ought to Be Decided By Domestic Laws.
• Chap. XX.: That We Ought Not to Decide By the Principles of the Civil Law, Those Things Which Belong to the Law of Nations.
• Chap. XXI.: That We Should Not Decide By Political Laws, Things Which Belong to the Law of Nations.
• Chap. XXII.: The Unhappy State of the Ynca Athualpa.
• Chap. XXIII.: That When, By Some Circumstance, the Political Law Becomes Destructive to the State, We Ought to Decide By Such a Political Law As Will Preserve It, Which Sometimes Becomes a Law of Nations.
• Chap. XXIV.: That the Regulations of the Police Are of a Different Class From Other Civil Laws.
• Chap. XXV.: That We Should Not Follow the General Disposition of the Civil Law, In Things Which Ought to Be Subject to Particular Rules Drawn From Their Own Nature.
• Book XXVII.: Of the Origin and Revolutions of the Roman Laws On Successions.
• Chap. I.
• Book XXVIII. Of the Origin and Revolutions of the Civil Laws Among the French.
• Chap. I.: Different Character of the Laws of the Several People of Germany.
• Chap. II.: That the Laws of the Barbarians Were All Personal.
• Chap. III.: Capital Difference Between the Salic Laws and Those of the Visigoths and Burgundians.
• Chap. IV.: In What Manner the Roman Law Came to Be Lost In the Country Subject to the Franks, and Preserved In That Subject to the Goths and Burgundians.
• Chap. V.: The Same Subject Continued.
• Chap. VI.: How the Roman Law Kept Its Ground In the Demesne of the Lombards.
• Chap. VII.: How the Roman Law Came to Be Lost In Spain.
• Chap. VIII.: A False Capitulary.
• Chap. IX.: In What Manner the Codes of Barbarian Laws, and the Capitularies Came to Be Lost.
• Chap. X.: The Same Subject Continued.
• Chap. XI.: Other Causes of the Disuse of the Codes of Barbarian Laws, As Well As of the Roman Law, and of the Capitularies.
• Chap. XII.: Of Local Customs. Revolution of the Laws of Barbarous Nations, As Well As of the Roman Law.
• Chap. XIII.: Difference Between the Salic Law, Or That of the Salian Franks, and That of the Ripuarian Franks, and Other Barbarous Nations.
• Chap. XIV.: Another Difference.
• Chap. XV.: A Reflection.
• Chap. XVI.: Of the Ordeal, Or Trial By Boiling Water, Established By the Salic Law.
• Chap. XVII.: Particular Notions of Our Ancestors.
• Chap. XVIII.: In What Manner the Custom of Judicial Combats Gained Ground.
• Chap. XIX.: A New Reason of the Disuse of the Salic and Roman Laws, As Also of the Capitularies.
• Chap. XX.: Origin of the Point of Honour.
• Chap. XXI.: A New Reflection Upon the Point of Honour Among the Germans.
• Chap. XXII.: Of the Manners Relative to Judicial Combats.
• Chap. XXIII.: Of the Code of Laws On Judicial Combats.
• Chap. XXIV.: Rules Established In the Judicial Combat.
• Chap. XXV.: Of the Bounds Prescribed to the Custom of Judicial Combats.
• Chap. XXVI.: Of the Judiciary Combat Between One of the Parties, and One of the Witnesses.
• Chap. XXVII.: Of the Judicial Combat Between One of the Parties, and One of the Lord’s Peers. Appeal of False Judgment.
• Chap. XXVIII.: Of the Appeal of Default of Justice.
• Chap. XXIX.: Epoch of the Reign of St. Lewis.
• Chap. XXX.: Observations On Appeals.
• Chap. XXXI.: The Same Subject Continued.
• Chap. XXXII.: The Same Subject Continued.
• Chap. XXXIII.: The Same Subject Continued.
• Chap. XXXIV.: In What Manner the Proceedings At Law Became Secret.
• Chap. XXXV.: Of the Costs.
• Chap. XXXVI.: Of the Public Prosecutor.
• Chap. XXXVII.: In What Manner the Institutions of St. Lewis Fell Into Oblivion.
• Chap. XXXVIII.: The Same Subject Continued.
• Chap. XXXIX.: The Same Subject Continued.
• Chap. Xl.: In What Manner the Judiciary Forms Were Borrowed From the Decretals.
• Chap. Xli.: Fiux and Reflux of the Ecclesiastic and Temporal Jurisdiction.
• Chap. Xlii.: the Revival of the Roman Law, and the Result Thereof. Change In the Tribunals.
• Chap. Xliii.: the Same Subject Continued.
• Chap. Xliv.: of the Proof By Witnesses.
• Chap. Xlv.: of the Customs of France.
• Book XXIX.: Of the Manner of Composing Laws.
• Chap. I.: Of the Spirit of a Legislator.
• Chap. II.: The Same Subject Continued.
• Chap. III.: That the Laws Which Seem to Deviate From the Views of the Legislator, Are Frequently Agreeable to Them.
• Chap. IV.: Of the Laws Contrary to the Views of the Legislator.
• Chap. V.: The Same Subject Continued.
• Chap. VI.: That Laws Which Appear the Same, Have Not Always the Same Effect.
• Chap. VII.: The Same Subject Continued. Necessity of Composing Laws In a Proper Manner.
• Chap. VIII.: That Laws Which Appear the Same, Were Not Always Made Through the Same Motive.
• Chap. IX.: That the Greek and Roman Laws Punished Suicide, But Not Through the Same Motive.
• Chap. X.: That Laws Which Seem Contrary, Proceed Sometimes From the Same Spirit.
• Chap. XI.: How We Are to Judge of the Difference of Laws.
• Chap. XII.: That Laws Which Appear the Same, Are Sometimes Really Different.
• Chap. XIII.: That We Must Not Separate Laws From the End For Which They Were Made. of the Roman Laws On Theft.
• Chap. XIV.: That We Must Not Separate the Laws From the Circumstances In Which They Were Made.
• Chap. XV.: That Sometimes It Is Proper the Law Should Amend Itself.
• Chap. XVI.: Things to Be Observed In the Composing of Laws.
• Chap. XVII.: A Bad Method of Giving Laws.
• Chap. XVIII.: Of the Ideas of Uniformity.
• Chap. XIX.: Of Legislators.
• Book XXX.: Theory of the Feudal Laws Among the Franks, In the Relation They Bear to the Establishment of the Monarchy.
• Chap. I.: Of Feudal Laws.
• Chap. II.: Of the Source of Feudal Laws.
• Chap. III.: The Origin of Vassalage.
• Chap. IV.: The Same Subject Continued.
• Chap. V.: Of the Conquests of the Franks.
• Chap. VI.: Of the Goths, Burgundians, and Franks.
• Chap. VII.: Different Ways of Dividing the Land.
• Chap. VIII.: The Same Subject Continued.
• Chap. IX.: A Just Application of the Law of the Burgundians and of That of the Visigoths In Relation to the Division of Lands.
• Chap. X.: Of Servitudes.
• Chap. XI.: The Same Subject Continued.
• Chap. XII.: That the Lands Belonging to the Division of the Barbarians Paid No Taxes.
• Chap. XIII.: Of Taxes Paid By the Romans and Gauls, In the Monarchy of the Franks.
• Chap. XIV.: Of What They Called Census.
• Chap. XV.: That What They Called Census Was Raised Only On the Bondmen, and Not On the Freemen.
• Chap. XVI.: Of the Feudal Lords Or Vassals.
• Chap. XVII.: Of the Military Service of Freemen.
• Chap. XVIII.: Of the Double Service.
• Chap. XIX.: Of Compositions Among the Barbarous Nations.
• Chap. XX.: Of What Was Afterwards Called the Jurisdiction of the Lords.
• Chap. XXI.: Of the Territorial Jurisdiction of the Churches.
• Chap. XXII.: That the Jurisdictions Were Established Before the End of the Second Race.
• Chap. XXIII.: General Idea of the Abbé Du Bos’ S Book On the Establishment of the French Monarchy In Gaul.
• Chap. XXIV.: The Same Subject Continued. Reflection On the Main Part of the System.
• Chap. XXV.: Of the French Nobility.
• Book XXXI.: Theory of the Feudal Laws Among the Franks, In the Relation They Bear to the Revolutions of Their Monarchy.
• Chap. I.: Changes In the Offices and In the Fiefs. of the Mayors of the Palace.
• Chap. II.: How the Civil Government Was Reformed.
• Chap. III.: Authority of the Mayors of the Palace.
• Chap. IV.: Of the Genius of the Nation In Regard to the Mayors.
• Chap. V.: In What Manner the Mayors Obtained the Command of the Armies.
• Chap. VI.: Second Epocha of the Humiliation of Our Kings of the First Race.
• Chap. VII.: Of the Great Offices and Fiefs Under the Mayors of the Palace.
• Chap. VIII.: In What Manner the Allodial Estates Were Changed Into Fiefs.
• Chap. IX.: How the Church-lands Were Converted Into Fiefs.
• Chap. X.: Riches of the Clergy.
• Chap. XI.: State of Europe At the Time of Charles Martel.
• Chap. XII.: Establishment of the Tithes.
• Chap. XIII.: Of the Election of Bishops and Abbots.
• Chap. XIV.: Of the Fiefs of Charles Martel.
• Chap. XV.: The Same Subject Continued.
• Chap. XVI.: Confusion of the Royalty and Mayoralty. the Second Race.
• Chap. XVII.: A Particular Circumstance In the Election of the Kings of the Second Race.
• Chap. XVIII.: Charlemaign.
• Chap. XIX.: The Same Subject Continued.
• Chap. XX.: Lewis the Debonnaire.
• Chap. XXI.: The Same Subject Continued.
• Chap. XXII.: The Same Subject Continued.
• Chap. XXIII.: The Same Subject Continued.
• Chap. XXIV.: That the Freemen Were Rendered Capable of Holding Fiefs.
• Chap. XXV.: The Principal Cause of the Humiliation of the Second Race. Changes In the Allodia.
• Chap. XXVI.: Changes In the Fiefs.
• Chap. XXVII.: Another Change Which Happened In the Fiefs.
• Chap. XXVIII.: Changes Which Happened In the Great Offices, and In the Fiefs.
• Chap. XXIX.: Of the Nature of the Fiefs After the Reign of Charles the Bald.
• Chap. XXX.: The Same Subject Continued.
• Chap. XXXI.: In What Manner the Empire Was Transferred From the Family of Charlemaign.
• Chap. XXXII.: In What Manner the Crown of France Was Transferred to the House of Hugh Capet.
• Chap. XXXIII.: Some Consequences of the Perpetuity of Fiefs.
• Chap. XXXIV.: The Same Subject Continued.

CHAP. XIV.

In what Instances Marriages between Relations should be regulated by the Laws of Nature; and in what Instances by the Civil Laws.

WITH regard to the prohibition of marriage between relations, it is a thing extremely delicate, to fix exactly the point at which the laws of nature stop, and where the civil laws begin. For this purpose, we must establish some principles.

The marriage of the son with the mother confounds the state of things: the son ought to have an unlimited respect to his mother, the wife an unlimited respect for her husband; therefore the marriage of the mother to her son would subvert the natural state of both.

Besides, nature has forwarded in women the time in which they are able to have children, but has retarded it in men; and, for the same reason, women sooner lose this ability, and men later. If the marriage between the mother and the son were permitted, it would almost always be the case, that when the husband was capable of entering into the views of nature, the wife would be incapable.

The marriage between the father and the daughter is contrary to nature, as well as the other; but it is not less contrary, because it has not these two obstacles. Thus the Tartars, who may marry their daughters* , never marry their mothers, as we see in the accounts we have of that nation† .

It has ever been the natural duty of fathers to watch over the chastity of their children. Intrusted with the care of their education, they are obliged to preserve the body in the greatest perfection, and the mind from the least corruption; to encourage whatever has a tendency to inspire them with virtuous desires, and to nourish a becoming tenderness. Fathers, always employed in preserving the morals of their children, must have a natural aversion to every thing that can render them corrupt. Marriage, you will say, is not a corruption: but before marriage they must speak, they must make their persons beloved, they must seduce: it is this seduction which ought to inspire us with horror.

There should be therefore an unsurmountable barrier between those who ought to give the education, and those who are to reeeive it; in order to prevent every kind of corruption, even though the motive be lawful. Why do fathers so carefully deprive those who are to marry their daughters, of their company and familiarity?

The horror that arises against the incest of the brother with the sister, should proceed from the same source. The desire of fathers and mothers to preserve the morals of their children and families untainted, is sufficient to inspire their offspring with a detestation of every thing that can lead to the union of the two sexes.

The prohibition of marriage between cousin-germans, has the same original. In the early ages, that is, in the times of innocence; in the ages when luxury was unknown, it was customary for children* , upon their marriage, not to remove from their parents, but to settle in the same house: as a small habitation was at that time sufficient for a large family: the children* of two brothers, or cousin-germans, were considered both by others and themselves, as brothers. The estrangement then between the brothers and sisters, as to marriage† , subsisted also between the cousin-germans.

These principles are so strong and so natural, that they have had their influence almost over all the earth, independently of any communication. It was not the Romans who taught the inhabitants of Formosa‡ , that the marriage of relations of the fourth degree was incestuous: it was not the Romans that communicated this sentiment to the Arabs∥ : it was not they who taught it to the inhabitants of the Maldivian islands§ .

But if some nations have not rejected marriages between fathers and children, sisters and brothers, we have seen in the first book, that intelligent beings do not always follow the law of nature. Who could have imagined it! Religious ideas have frequently made men fall into these mistakes. If the Assyrians and the Persians married their mothers, the first were influenced by a religious respect for Semiramis; and the second did it, because the religion of Zoroaster gave a preference** to these marriages. If the Ægyptians married their sisters, it proceeded from the wildness of the Ægyptian religion, which consecrated these marriages in honour of Isis. As the spirit of religion leads us to attempt whatever is great and difficult, we cannot infer that a thing is natural, from its being consecrated by a false religion.

The principle which informs us that marriages between fathers and children, between brothers and sisters, are prohibited, in order to preserve natural modesty in families, will help us to the discovery of those marriages that are forbidden by the law of nature, and of those which can be so only by the civil law.

As children dwell, or are supposed to dwell in their father’s house, and consequently the son-in-law with the mother-in-law, the father-in-law with the daughter-in-law, or wife’s daughter; the marriage between them is forbidden by the law of nature. In this case the resemblance has the same effect as the reality, because it springs from the same cause: the civil law neither can, nor ought to permit these marriages.

There are nations, as we have already observed, amongst whom cousin germans are considered as brothers, because they commonly dwell in the same house: there are others, where this custom is not known. Among the first, the marriage of cousingermans ought to be regarded as contrary to nature; not so among the others.

But the laws of nature cannot be local. Therefore, when these marriages are forbidden, or permitted, they are, according to the circumstances, permitted or forbidden by a civil law.

It is not a necessary custom for the brother-in-law and the sister-in-law to dwell in the same house. The marriage between them is not then prohibited to preserve chastity in the family; and the law which forbids or permits it, is not a law of nature, but a civil law, regulated by circumstances, and dependent on the customs of each country: these are cases in which the laws depend on the morals or customs of the inhabitants.

The civil laws forbid marriages, when by the customs received in a certain country they are found to be in the same circumstances as those forbidden by the law of nature; and they permit them when this is not the case. The prohibitions of the laws of nature are invariable, because the thing on which they depend is invariable; the father, the mother, and the children, necessarily dwell in the same house. But the prohibitions of the civil laws are accidental, because they depend on an accidental circumstance; cousin-germans and others dwelling in the house by accident.

This explains why the laws of Moses, those of the Ægyptians* , and of many other nations, permitted the marriage of the brother-in-law with the sister-in-law; whilst these very marriages were disallowed by other nations.

In the Indies they have a very natural reason for admitting this sort of marriages. The uncle is there considered as the father, and is obliged to maintain and educate his nephew, as if he were his own child: this proceeds from the disposition of these people, which is good-natured and full of humanity. This law, or this custom, has produced another; if a husband has lost his wife, he does not fail to marry her sister: which is extremely natural, for his new consort becomes the mother of her sister’s children, and not a cruel step-mother.

[* ]This law is very ancient amongst them. Attila, says Priscus in his embassy, stopt in a certain place to marry Esca his daughter: a thing permitted, he adds, by the Laws of the Scythians, page 22.

[† ]Hist. of the Tartars, part 3. page 236.

[* ]It was thus amongst the ancient Romans.

[* ]Amongst the Romans they had the same name, the cousin-germans were called brothers.

[† ]It was thus at Rome in the first ages, till the people made a law to permit them; they were willing to favour a man extremely popular, who had married his cousin-german. Plutarch’s Treatise, intitled, Questions concerning the affairs of the Romans.

[‡ ]Collection of Voyages to the Indies, vol. 5. part 1. An account of the state of the isle of Formosa.

[∥ ]Koran, chap. of women.

[§ ]See Francis Pirrard.

[** ]They were considered as more honourable. See Philo, de specialibus legib. quæ pertinent ad præcepta decalogi. Paris, 1640. page 778.

[* ]See Law 8. of the Code de incestis & inutilibus nuptiis.