INTRODUCTORY. 25 



contemplation, for which science gives us little or no help. 

 To define and demonstrate, so as to produce general con- 

 viction, is to a large extent quite impossible. To gain 

 understanding here is a task which each thinking and 

 contemplating mind is bound to perform for itself alone. 

 An awakening to the consciousness that there are two 

 realities in and around us which language and common- 

 sense unconsciously recognise, but continually inter- 

 mingle, marks probably the first important stage in the 

 history of philosophy, and accordingly we find already 

 with the great philosophers of Greece, notably with Plato, 20. 



Twofold 



due recognition of this twofold aspect of the real, and a aspect of 



the Real first 



continued striving to find an appropriate expression for it. 

 We owe to Plato the greater part of the terms by 

 which this central problem of philosophy is put before 

 us in the writings of ancient and modern thinkers. He 

 created at least one half of the vocabulary of mental 

 philosophy; he first put prominently forward and ex- 

 pressed in words the conception that there is a world of 

 ideas which has a definite existence not only in but 

 above and outside of the world of material things. In 

 speaking of that which is real or exists (TO ov) he puts 

 forward the notion of that which is really (not only 

 apparently) real (TO OVTWC ov), and likewise the comple- 

 mentary notion that, besides the real, there exists some- 

 thing which is not real (TO ^77 ov), and which, by its 

 admixture with the truly real, deprives the latter of a 

 portion of its true or pure reality, reducing it to an 

 appearance or semblance. He also tries to answer the 

 question: What is the nature or essence of the truly 

 real ? All these reflections, put forward in the Platonic 



