SECT. 21.] Chance, Causation, and Design. 259 



be defined as any agent which produces a chance or random 

 arrangement, I am afraid there can be little doubt that it 

 was this agent that was at work in the case in question. 

 The arrangement of male and female births presents, so far 

 as we can see, one of the most perfect examples of chance : 

 there is ultimate uniformity emerging out of individual 

 irregularity : all the runs or successions of each alternative 

 are duly represented : the fact of, say, five sons having been 

 already born in a family does not seem to have any certain 

 effect in diminishing the likelihood of the next being a son, 

 and so on. Such a nearly perfect instance of independent 

 events is comparatively very rare in physical phenomena. 

 It is all that we can claim from a chance arrangement 1 . The 

 only other interpretation I can see is to suggest that there 

 was but one agent who might, like any one of us, have either 

 tossed up or designed, and we have to ascertain which course 

 he probably adopted in the case in question. Here too, if 

 we are to judge of his mode of action by the tests we should 

 apply to any work of our own, it would certainly look very 

 much as if he had adopted some scheme of tossing. 



21. The simple fact is that any rational attempt to 



1 That is, if we look simply to a preponderance, agencies are at 

 statistical results, as Arbuthnott did, once set in motion which tend to 

 and as we should do if we were ex- redress the balance. This is a modi- 

 amining the tosses of a penny. If fication and improvement of the older 

 the remarkable theory of Dr Diising theory, that the relative age of the 

 (Die Regulierung des Geschlechts- parents has something to do with 

 verlmltnisses . . . Jena, 1834) be con- the sex of the offspring, 

 firmed, the matter would assume Quetelet (Letters, p. 61) has at- 

 a somewhat different aspect. He at- tempted to prove a proposition about 

 tempts to show, both on physio- the succession of male and female 

 logical grounds, and by analysis of births by certain experiments sup- 

 statistics referring to men and posed to be tried upon an urn with 

 animals, that there is a decidedly black and white balls in it. But 

 compensatory process at work. That this is going too far. (See the note 

 is, if for any cause either sex attains at the end of this chapter.) 



172 



