It is clear that Wolff must have already had made preparations for the Vernünfftige Gedancken von dem gesellschafftlichen Leben der Menschen und insonderheit dem geimeinen Wesen, when he published the previous title in the ”Reasonable thoughts” -series. Wolff's German ethics concentrated on the individual in abstraction from his social surroundings, but the current book promises to correct this mistake.
Wolff accepts the tradition of contractual origin of societies, which emphasises the essentialy individual nature of human beings and which was later criticised by Hegel. The story begins from an imagined point where individuals have not yet formed any societies. If human beings could provide for themselves, the story would also end here, but they have various needs for which they require the help of others. Thus arises the need for contracts, where one person offers what the other desires. Some of these contracts call for the persons involved to live together as a unit, and such units and the interpersonal relations within them are what Wolff is describing in the book.
The origin story provides Wolff already with some general principles that are valid of all societies. Every society has been generated for the purpose of promoting the well-being of its occupants – hence, the end of the society lies in the individuals and their common good. When the society strives to do something for the good of its members, it is morally mound by the same natural laws as the individuals themselves. If the society breaches those laws, individuals have then no duty to remain within that society. Finally, all of these societies can be regarded as individuals in their own right, and every society should be independent of other societies of the same sort.
Wolff calls the study of these societies politics, but the first half of the book is actually dedicated to what was traditionally known as economics after a pseudo-Aristotelian book of the same name. This was not economics in the modern sense – a study of e.g. commerce – but study of oikos or household, while politics was restricted to a study of polis or community. Wolff's book quickly turns into a description and justification of the customs of his own culture, the 18th century Germany. Thus, we hear that a household contains three types of relations: those between a husband and a wife, those between parents and children and those between masters and servants.
The traditionality of the book can be seen in Wolff's definition of marriage as a union of a man and a woman for the sake of conceiving and educating children. Wolff's justification of the tradition of marriage betrays a common ambivalent relation to sexuality. Wolff admits that the desire for sex is natural as the necessary means for the reproduction of human species – even a person in an ideal state of knowledge would want to have sex. Thus, having sex is even a duty: once you are capable, just go and do it.
Then again, Wolff thinks sex is good only as a means for reproduction. Especially the pleasure connected to sex exists only for the sake of hinting that conception of children is good. Hence, any sex that cannot lead to the birth of children is by definition forbidden. Wolff explicitly mentions e.g. bestiality, prostitution and homosexuality, but refrains from describing all possible sexual vices in order to avoid giving any bad influences. And who is the worse sinner, the prostitute or the client? Wolff's definite answer is the prostitute: while the client is governed by his sexual impulses, the prostitute could use reason, but chooses to make sin for the sake of money.
Often the defenders of traditional marriage shy away from the unwanted consequences of their premisses. Wolff takes his premisses seriously and denies even all heterosexual sex that cannot lead to conception. Thus, sex and marriage with an elderly and generally with an infertile person is forbidden. Still, Wolff does allow marriage continue throughout the life time of the married persons, so that they can take care of one another in their old age.
Mere conception of children is not enough, but one is duty-bound to take care of the children until they can take care of themselves. Hence, the need for marriage. Because one is committed only to raise one's own children, women should not have many partners, Wolff says – otherwise, we could not determine who the father is. In principle men could have many wives, but children of one wife are enough for one man to provide for – shortage of cash is the only reason for dismissing polygyny.
Husband and wife must then take care of their children. Here Wolff can conveniently just copy what he has said in his ethical writings, because duties for the welfare of others coincide with the duties for oneself: one must feed and cloth the child, and especially one must educate him or her, both in intelligence and will. Wolff shows some progressiveness, when he urges the parents to depend more on the children's intelligence than on beating and punishments – that is, when the children start to understand things better. When the children can finally provide for themselves, the duty of the parents stops, but the children are for the rest of their lives committed to respecting their parents for their kind deeds.
If the parents work for the good of the children, the servants are hired to work for their masters. Although the masters thus appear to be more in need, it is actually the servants who have the worse position: servants cannot provide for themselves and so they must sell their services for their living. What servants are to do is mostly decided by the contract made with the master – they just have to do it obediently and the master has to see that the servants are not overtasked. Wolff even allows the possibility that servants (or slaves) would be owned by the master, who could then also sell them to others. Wolff restricts slavery only to persons whose happiness essentially requires external governance. We immediately recognise a common excuse for the enslavement of Africans: they just couldn't manage themselves.
Wolff lived in an age when social relations were for the most part hierarchic. Thus, even in household there must be one person leading others. Children are still not fully rational and so are to obey their parents, while the servants are bound by the contract to obey their masters. When it comes to mixing children and servants, Wolff expressly instructs to avoid it. Children might disturb the work of the servants, but the true reason for Wolff's command appears to be the fear of corrupting influence that servants as persons of lower status might have on children.
The case of husband and wife is more interesting. The result is, of course, determined by the gender roles of the time. Husband or the lord of the house is to be the final master over the household, while the lady of the house is relegated into the position of a trusted advisor, who knows the affairs of the household best, and a representative of the lord, whom the other occupants must obey. Yet, Wolff admits that in principle men and women are not that different. Women are just more bound to the children, and it is customarily the men who have to provide for their families. Hence, the men know more about the ways of the world and should therefore rule the household. Although Wolff's argument is meant to uphold the status quo, it leaves open the option that under different customs women might have the opportunity to educate themselves and become as capable of taking care of the household as men are.
Wolffian economics shows then barely a hint of progression from the traditional trappings. We shall see if things fare better with the actual politics.