Pearl: Dynamic Evolution 



255 



have been published in various journals Thus on p. 85 he tables the mean age 



devoted to live-stock or fancy breeding of fifty-eight sires of 2:10 stallions in 



interests. He has applied his thesis the following way : 



Sires of 2:10 Stallions 



45 Sires with records, average age 9.8 years 



13 Sires without records, average age 13 . 6 years 



58 Sires of Stalhons, average age 10 . 7 1 years 



to trotting horses, setter dogs, Holstein He then shows that the mean age of 



cattle, and human beings. The first 1,000 trotting horse sires in general 



fourth of the book is devoted to an (prestmiably a random sample, but this 



exposition of the theory in general is not entirely clear) is 10.43 years. I 



terms. The discussion is of a most leave these figures to the consideration 



fundamental character. It has as its of the biometrician, with only the addi- 



only initial assumption existence of tional quotation of Mr. Redfield's 



matter and energy. From that some- comment upon the table : "The striking 



what unpromising, or at least very raw, thing about the above table is the fact 



material there is developed in some fifty that one group of sires falls below this 



odd pages, by pure ratiocination, a full (the general) average while the other 



blown theory of heredity.- This theory group is considerably above it. As 



consists essentially of the thesis which age means time, and time is a factor 



has already been outlined. The at- of energy and not of anything else, any 



tempt to ground it on elementary prin- variation, other than a mere accidental 



ciples of physics and pure logic need one, in the average age of a group of 



not detain us. sires from the normal average, has 



The rest of the book is nearer the reference solely to work performed by 



ground. It consists in an application those sires before reproduction, 



of the theory to selected facts in the Whether the present variation is due 



breeding history of the animal forms to accident or to the operation of a law 



mentioned in the preceding paragraph, of nature we may determine by examin- 



Mr. Redfield apparently regards these ing the sires in detail and learning what 



chapters as an exposition of the results relationship existed between the ages 



of different tests of the vahdity of the of the dilTerent ones and the work they 



theory. In any sense which a trained performed." 



scientist would regard as critical none To speak about laws of nature on 



of the material presented can be looked such a basis of fact is, to put it quite 



upon as furnishing a definite test of mildly, a thoroughly optimistic piece 



the theory. of business. 



It would require altogether too much 



space to discuss critically all the points contradictions disregarded 



of alleged fact and their interpretation In the second place all unconformable 



brought out in this book. It will facts, and all ways of looking at the 



perhaps be more useful to point out facts different from the author's way 



wherein the methods of " investigation " are totally disregarded. For example, 



followed in general by Mr. Redfield in the discussion of Laverack's setters 



seem to be faulty. In the first place the results which that breeder got are 



our author apparently has no concep- interpreted as solel}^ due to the fact 



tion of the meaning of random sampling that he hunted his dogs and bred them 



and the errors connected therewith, relatively late in life. There is not the 



Many of his comparisons are essentially slightest real evidence that either of 



statistical in their nature, but there these two things had any more than a 



is not a "probable error" in the book, very minor part, if any, in accounting 



2 Incidentally in the process there are chipped off some real gems of thought. I would espe- 

 cially recommend to the consideration of professional philosophers this last sentence on p. 3: 

 "Causes are forces acting upon matter." 



