66 NATURAL INHERITANCE. [CHAP. 



Order in Apparent Chaos. I know of scarcely any- 

 thing so apt to impress the imagination as the wonderful 

 form of cosmic order expressed by the " Law of Fre- 

 quency of Error." The law would have been personified 

 by the Greeks and deified, if they had known of it. It 

 reigns with serenity and in complete self-effacement 

 amidst the wildest confusion. The huger the mob, and 

 the greater the apparent anarchy, the more perfect is its 

 sway. It is the supreme law of Unreason. Whenever 

 a large sample of chaotic elements are taken in hand 

 and marshalled in the order of their magnitude, an un- 

 suspected and most beautiful form of regularity proves 

 to have been latent all along. The tops of the mar- 

 shalled row form a flowing curve of invariable pro- 

 portions ; and each element, as it is sorted into place, 

 finds, as it were, a pre-ordained niche, accurately 

 adapted to fit it. If the measurement at any two 

 specified Grades in the row are known, those that will 

 be found at every other Grade, except towards the 

 extreme ends, can be predicted in the way already 

 explained, and with much precision. 



Problems in the Law of Error. All the properties of 

 the Law of Frequency of Error can be expressed in 

 terms of Q, or of the Prob: Error, just as those of a 

 circle can be expressed in terms of its radius. The 

 visible Schemes are not, however, to be removed too 

 soon from our imagination. It is always well to retain 

 a clear geometric view of the facts when we are dealing 

 with statistical problems, which abound with dangerous 



