1 68 POPULAR SCIENCE MONTHLY. 



at about this same time, who were exceedingly weak. These were 

 John II. and Henry IV. They are not in the direct line under dis- 

 cussion at present, but it is interesting to see that John II. was a 

 grandson of John I. just noted for his weaknesses and the causes of 

 this temporary running out and subsequent rejuvenation in Ferdinand 

 and Isabella will be discussed later. 



During the early centuries of Christian Spain the conditions of 

 the times were such that every sovereign was obliged to defend his 

 right to the throne against the jealousies of his family, so that almost 

 constant wars were being waged among the nearest kin and it was 

 practically impossible that several generations of weak and incom- 

 petent kings should not have been wrested from the throne. This 

 factor of natural selection undoubtedly did much to insure the strength 

 of the stock. 



The long minorities of the sovereigns of Castile and Aragon which 

 occurred time and again during these centuries have always been con- 

 sidered by all historians as one of her greatest misfortunes, leading 

 to intrigues, civil wars and disasters; affairs being put in a healthy 

 condition again only when the king himself was old enough to take 

 things in his own hands. 



This and the fact that the country invariably gained ground under 

 good rulers and just as certainly lost under weak ones make it evident 

 how much more important the king was in those days and under those 

 conditions than he has been in England, for instance, where the pro- 

 gress has been due to the people as a whole, especially her aristocracy 

 and upper classes.* 



Such a long line of great rulers as this, such an almost unbroken 

 repetition of great physical and mental strength is almost unparalleled, 

 save by Portugal, in all history. If there is much in heredity it 

 must certainly be necessary here to show that the dynasty was con- 

 tinually maintained by the introduction of just such great qualities 

 either from the best part of its own stock or from outside families. 



We can discuss twenty marriages in the direct line. The following 

 fourteen can be seen to have introduced stock equally vigorous and 

 able. These fourteen are those of Sancho II., Ferdinand I. of Leon, 

 Alfonso VI., Ferdinand II., Alfonso IX., Ferdinand IV., Alfonso II., 

 Henry III., Don John II. of Aragon, Ferdinand and Isabella, Johanna 

 'the Mad.' These were scattered along the course and sufficiently 

 account for the perpetuation of the strain. Many of these unions 

 were remarkably good, being well backed on all sides. Of the other 

 six, four were 'obscure,' tending that much to dilute the distinguished 

 qualities. 



* Conf. Havelock Ellis, ' Study of British Genius,' Popular Science 

 Monthly. (Geniuses have come from the upper classes.) 



