I attribute in part to the constant struggle between the rival families, between brothers of the same family and other close relatives, in their jealous greed for power and domain, thus keeping up a struggle for existence, capable of showing itself in results, and partly to fortuitous chance endowing the heir to the throne with the qualities of the stronger rather than the weaker of his ancestry. The number of weak or indolent is correspondingly small, though high temper, jealousy and ambition are present in nearly all.
I find about six persons to whom the terms feeble, characterless and indolent, are applied. Two of these, Andrew II., King of Hungary, and Ferdinand IV., of Castile, are apart from the others. The remaining four are very closely related, being father, son, nephew and his son. These are John I., John II., Henry IV. of Castile and Ferdinand I. of Aragon.
The family had already existed twelve generations before these characteristics appeared in it. In the tenth generation one of the greatest names is found in Ferdinand IV., and even in the nineteenth and twenty-first generations some of the best and most vigorous and ambitious appear in Ferdinand, Isabella and the Emperor Charles, all of whom were the descendants of the privileged few with a pedigree practically entirely of this sort extending back through more than twenty generations on all sides, and including many thousands of nobles titles.
These names which close the group are as great as those which opened it. How can this be if the assumption of rank and power is to lead to degeneration? It may be argued that the necessity for action in these times of incessant strife obliged the individuals to be energetic and so the characters were the product of their times, but we have seen that the selection alone would produce this. Furthermore, against the environment explanation we must remember the great number of able and vigorous men who appear much later in history in other countries and the descendants of forty instead of twenty generations of blue-bloods. The modern Saxe-Coburg-Gotha chart is almost entirely free from weaknesses and indolence.
The insanity apparently starts in Peter the Cruel. We have seen how his character might well have been the result of a combination of a large number of cruel persons. This insanity continually reappeared in Spain, where one finds it most rampant. It occasionally appeared in Austria, where it was less often introduced. It probably was also the origin of the Plantagenet neurosis, the full history of which I have not yet had time to study with any completeness.
