Without the union of man and woman there can be no multiplication of the human species, but the number of these unions alone is not the only prerequisite of this multiplication: it is necessary in addition to bring [children] up with care, and to have the means of supporting them, otherwise they will either die before the natural time or they will be useless and of little value to their country… . How does Constantinople benefit from its populousness if every third year the contagion almost deprives the city of its inhabitants? Plague and disease arise in fact from the closeness and discomfort of the dwellings, the filth and dirt of living conditions and lack of care on the part of the government to keep the cities clean and the air purified, and other similar causes. All these things make it difficult to rear children, and although great numbers are born, comparatively few survive or grow to be men of any value… . Thus of the two conditions conducive to the propagation of the species, generation and upbringing, a high proportion of marriages may help the one but will certainly hinder the other… . It is not sufficient, therefore, for a prince to encourage marriages and fertility if he does not also assist the rearing and upkeep of the young, by charity towards the poor and by helping the needy and those who have not the means to marry their daughters or instruct their sons or to support themselves and their families.