CHAPTER III. 



THE PROBLEMS PRESENTED. 



In his classical work on Heredity, Professor J. Arthur Thomson 

 exhausts the evidence on Lamarckism available then (1908) in 

 a manner worthy of the summing-up of an English judge. This 

 is presented to the jury of the biological world and they are still 

 considering it. Their verdict and his sentence are not yet delivered, 

 and it may be they will still be long delayed. One might almost 

 use the words of Professor Bateson, previously quoted, " on our 

 present knowledge the matter is talked out." 



I will make one prophecy in this volume and predict that the 

 fourth edition of this work in 1930 will contain the verdict of the 

 jury and sentence of the distinguished judge to the effect that m 

 the case Lamarck v. Weismann the plaintiff has won. As in the 

 Great War the Old Contemptibles held their line with the utmost 

 difficulty against the disciplined hosts of the greatest army ever 

 known till then, and yet the latter found their First Battle of the 

 Marne, so perchance it may be in the present struggle. 



I introduce this chapter with an important passage from the 

 above work on the Logical position of the Argument, in which 

 the two possible methods of establishing the affirmative position 

 of Lamarck are given ; these are, first, actual experimental proof 

 of transmission, and, second, a collection of facts which cannot 

 be interpreted without the hypothesis of modification inheritance. 

 The words are : x " The neo- Lamar ckians have to show that the 'pheno- 

 mena they adduce as illustrations of modification-inheritance cannot 

 be interpreted as the results of selection operating on germinal variations. 

 In order to do this to the satisfaction of the other side, the neo- 

 Lamarckians must prove that the characters in question are outside 

 the scope of natural selection, that they are non-utilitarian and not 

 correlated with any useful characters — a manifestly difficult task. 

 The neo- Darwinians, on the other hand, have to prove that the pheno- 

 mena in question cannot be the results of modification-inheritance. 

 And this is in most cases impossible."* 



1 Heredity, 1908, p. 240. 



2 I prefer to state the above passage rather than that on page 179, which 

 is as follows : " The precise question is this : Can a structural change in the 

 body, induced by some change in use or disuse, or by a change in surrounding 

 influence, affect the germ-cells in such a specific or representative way that the 

 offspring will through its inheritance exhibit, even in a slight degree, the modifica- 

 tion which the parent acquired ? " (Italics in original). The question is very 

 precise and important, but I employ that given above in preference as lending 

 itself better to the line of inquiry followed here. 





