THE HISTORY OF THE SUBJECT 17 



domain of the processes of heredity. That which is termed 

 "Mneme" and "Engramm" is not further analyzed. Senion 

 expressly declines to discuss the kind of alterations in which 

 the physical or chemical nature of an "Engramm" consists. 

 Hence physiological analysis has not been advanced in any 

 way by Semon's new formation of words applied to long- 

 known facts. With a series of new expressions the originator 

 of the "Mneme doctrine" deceives himself, as well as a number of 

 his readers not endowed with the critical faculty, into supposing 

 that he has achieved a serious analysis. Of such, however, there 

 is not a trace. As can be. conceived, this way of treating the 

 manifestations of life has met with no further attention from the 

 physiological side. For indeed, what physiologist would con- 

 sider that the fact of muscle responding by a contraction to an 

 induction shock, or to any other stimulus, is sufficiently analyzed 

 by the explanation that we have the "Ekphorie" of a state of 

 excitation that was once previously produced by an original 

 stimulus of some unknown kind, and of which the living sub- 

 stance of the muscle, in consequence of its "Mneme," has retained 

 a latent "Engramm"? Here the deep gulf is apparent which 

 exists between the demands of a physiological analysis and the 

 futile explanation of the mneme doctrine. Physiological inves- 

 tigation must reject such a manner of treating its problems. 



With this the history of the doctrine of irritability enters into 

 its present phase of development. To future research remains 

 then the problem of further analyzing irritability, this common 

 property of living substance, and finally rendering it into its sim- 

 plest chemical and physical components. This last goal can only 

 be approached very gradually, step by step. With the analysis of 

 irritability we shall investigate life itself. In the following lec- 

 tures it will be my endeavor to show how far, with our present 

 knowledge, we can penetrate by this path into the great secret. 



