Read history through the nature of human society.
The solidarity born of kinship, alliance or clientship binds people to defend one another and to pursue common goals; it is strongest among those who live hard lives on the desert fringe, and royal authority is its natural aim.
A tribe that fights as one can overrun a wealthy city whose inhabitants have handed their defence to paid troops.
Ibn Khaldun presents as new an independent science whose object is human social organization: the conditions that necessarily arise when people live together, such as solidarity, rule, crafts, cities and learning.
Unlike rhetoric, which persuades, or political ethics, which prescribes, this science describes how societies actually behave, for instance why refined crafts flourish only in large cities.
A dynasty built on strong solidarity usually lasts about three generations, some 120 years: the founders keep the virtues of desert life, their sons preserve them by imitation, and grandsons raised in sedentary luxury forget what won power.
The founder’s grandsons rely on hired soldiers and heavier taxes until a tougher group from the margins replaces them and the cycle begins again.
A report must be judged not only by the reliability of those who transmitted it but by whether its content is possible given the nature of civilization; impossible numbers or events betray error, partisanship or credulity.
He rejects the claim that Moses counted 600,000 Israelite fighting men, arguing that so vast an army could neither be supplied nor deployed in such a land.