49. There is an abundant civilization (large population)
at the end of dynasties, and pestilences and
famines frequently occur then.
In the previous (discussion) 741 it has been established that, at the beginning, dynasties are inevitably kind in the exercise of their power and just in their administration. The reason is either their religion, when (the dynasty) is based upon religious propaganda, or their noble and benevolent attitude toward others, which is required by the desert attitude that is natural to dynasties (at the beginning).
A 742 kind and benevolent rule serves as an incentive to the subjects and gives them energy for cultural activities. (Civilization) will be abundant, and procreation will be vigorous. All this takes place gradually. The effects will become noticeable after one or two generations at best. At the end of two generations, the dynasty approaches the limit of its natural life 743 At that time, civilization has reached the limit of its abundance and growth.
It should not be objected here that it was stated before 744 that in the later (years) of a dynasty, there will be coercion of the subjects and bad government. This is correct, but it does not contradict what we have (just) said. Even though coercion makes its appearance at that time and the revenues decrease, the destructive influences of this situation on civilization will become noticeable only after some time, because things in nature all have a gradual development.
In the later (years) of dynasties, famines and pestilences become numerous. As far as famines are concerned, the reason is that most people at that time refrain from cultivating the soil. For, in the later (years) of dynasties, there occur attacks on property and tax revenue and, through customs duties, on trading.745 Or, trouble occurs as the result of the unrest of the subjects and the great number of rebels (who are provoked) by the senility of the dynasty to rebel. Therefore, as a rule, little grain is stored. The grain and harvest situation is not always good and stable from year to year. The amount of rainfall in the world differs by nature. The rainfall may be strong or weak, little or much. Grain, fruits, and (the amount of) milk given by animals varies correspondingly. Still, for their food requirements, people put their trust in what it is possible to store. If nothing is stored, people must expect famines. The price of grain rises. Indigent people are unable to buy any and perish. If for some years nothing is stored, hunger will be general.
The large number of pestilences has its reason in the large number of famines just mentioned. Or, it has its reason in the many disturbances that result from the disintegration of the dynasty. There is much unrest and bloodshed, and plagues occur. The principal reason for the latter is the corruption of the air (climate) through (too) large a civilization (population).746 It results from the putrefaction and the many evil moistures with which (the air) has contact (in a dense civilization). Now, air nourishes the animal spirit 747 and is constantly with it. When it is corrupted, corruption affects the temper of (the spirit). If the corruption is strong, the lung is afflicted with disease. This results in epidemics, which affect the lung in particular. (Even) if the corruption is not strong or great, - putrefaction grows and multiplies under (its influence), resulting in many fevers that affect the tempers, and the bodies become sick and perish. The reason for the growth of putrefaction and evil moistures is invariably a dense and abundant civilization such as exists in the later (years) of a dynasty. (Such civilization) is the result of the good government, the kindness, the safety, and the light taxation that existed at the beginning of the dynasty. This is obvious. Therefore, it has been clarified by science 748 in the proper place that it is necessary to have empty spaces and waste regions interspersed between civilized areas. This makes circulation of the air possible. It removes the corruption and putrefaction affecting the air after contact with living beings, and brings healthy air. This also is the reason why pestilences occur much more frequently in densely settled cities than elsewhere, as, for instance, in Cairo in the East and Fez in the Maghrib.
God determines whatever He wishes.