92 SELECTED ESSAYS FROM LAY SERMONS 



resisting mass of the oak, or the strong fabric of the tortoise, 

 and those broad disks of glassy jelly which may be seen 

 pulsating through the waters of a calm sea, but which drain 

 away to mere films in the hand which raises them out of 

 their element? 



Such objections as these must, I think, arise in the mind 

 of every one who ponders, for the first time, upon the con- 

 ception of a single physical basis of life underlying all the 

 diversities of vital existence; but I propose to demonstrate 

 to you that, notwithstanding these apparent difficulties, a 

 threefold unity — namely, a unity of power or faculty, a 

 unity of form, and a unity of substantial composition — does 

 pervade the whole living world. 



No very abstruse argumentation is needed, in the first 

 place to prove that the powers, or faculties, of all kinds of 

 living matter, diverse as they may be in degree, are substan- 

 tially similar in kind. 



Goethe has condensed a survey of all powers of mankind 

 into the well-known epigram: — 



"Warum treibt sich das Volk so und schreit? Es will sich ernahren 

 Kinder zeugen, und die nahren so gut es'vermag. 



* * * * 



Weiter bringt es kein Mensch, stelT er sich wie er auch will." 



'In physiological language this means, that all the multi- 

 farious and complicated activities of man 'are comprehen- 

 sible under three categories. Either they are immediately 

 directed towards the maintenance and development of the 

 body, or they effect transitory changes in the relative posi- 

 tions of parts of the body, or they tend towards the contin- 

 uance of the species. Even those manifestations of intellect, 

 of feeling, and of will, which we rightly name the higher 



