THE FOUNDATION OF EVOLUTION 



their esse is percipi their being is the being per- 

 ceived. The opposite school say that mind must 

 be a product of the ethereal energies, though they 

 do not tell us how the law of the conservation of 

 energy can be proved to hold in regard to the 

 production of the Eroica symphony or the " Divina 

 Commedia." The third school finds it impossible 

 to explain mind in terms of not-mind, or not-mind 

 in terms of mind, and regards both as manifesta- 

 tions of one Reality. This is the Spencer-Spinoza 

 school. Time is not yet when men shall cease to 

 discuss that Reality's ineffable name. For myself, 

 I hold it literally ineffable, unspeakable because 

 unknowable. 



Having thus attempted to survey the field of 

 philosophy, we may consider more in detail that 

 magnificent generalization which had been pro- 

 vided for Spencer by the labors of such men, 

 working both before and after the inception of 

 the evolutionary philosophy, as Helmholtz, Joule, 

 Mayer, Mohr, and Kelvin. Energy, as then un- 

 derstood, was distinct from and almost antithet- 

 ical to matter. Each was regarded as ultimate 

 and irresolvable. To-day, as we have seen, mat- 

 ter is not regarded as an ultimate, and the state- 

 ment of its conservation is merged in the newer 

 and greater dogma. But Spencer anticipated this 

 view nearly half a century ago, when radio-activity 

 and the new theory of matter were undreamed of. 

 Seeing that matter, as known to us, is none other 

 49 



