In former times some countries were so scrupulous in this matter, so severe, that if a child was crooked or deformed in body or mind, they killed it. The ancient Indians did so, according to Curtius, as did many other well-governed commonwealths, following the discipline of those times.

Formerly in Scotland, says Hector Boece, anyone afflicted with the falling sickness, madness, gout, leprosy or another dangerous disease likely to pass from father to son was immediately castrated; a woman was kept away from all company of men. If a woman with such a disease happened to be found pregnant, she and her unborn child were buried alive. This was done for the common good, lest the whole nation be harmed or corrupted.

A harsh sentence, you will say, and one that Christians should not employ; yet the matter deserves closer attention than it receives. For now our excessive leniency in this respect—allowing everyone who wishes to marry, giving too much freedom and indulgence to all sorts of people—has produced an immense confusion of hereditary diseases. No family is secure, scarcely anyone free of some grievous infirmity or other.

There is no selection: the eldest sons must always marry, like so many breeding stallions; or men must marry if they are rich, whether fools or simpletons, lame or maimed, impotent, intemperate, dissolute or worn out by debauchery. As the writer says, “They are commanded to be wise by hereditary right”: they must possess wisdom and ability by inheritance.

The result is that our offspring are corrupted. We have many people weak in body and mind, many deadly diseases raging among us, families in broken health: “parents, destroyers.” Our fathers are bad, and we are likely to be worse.