ACTUALITY 265 



subject-matter has undergone, and indeed retains evi- 

 dences of, this process of selection. 



Actuality. "Knowableness to mind" is moreover a 

 property which differentiates the actual world of our 

 experience from imaginary worlds in which the same 

 general laws of Nature are supposed to hold true. 

 Consider a world — Utopia, let us say — governed by all 

 the laws of Nature known and unknown which govern 

 our own world, but containing better stars, planets, 

 cities, animals, etc. — a world which might exist, but 

 it just happens that it doesn't. How can the physicist 

 test that Utopia is not the actual world? We refer to 

 a piece of matter in it; it is not real matter but it attracts 

 any other piece of (unreal) matter in Utopia according 

 to the law of gravitation. Scales and clocks constructed 

 of this unreal matter will measure wrong intervals, but 

 the physicist cannot detect that they are wrong unless 

 he has first shown the unreality of the matter. As soon 

 as any element in it has been shown to be unreal Utopia 

 collapses; but so long as we keep to the cycles of physics 

 we can never find the vulnerable point, for each element 

 is correctly linked to the rest of the cycle, all our laws 

 of Nature expressed by the cycle being obeyed in Utopia 

 by hypothesis. The unreal stars emit unreal light which 

 falls on unreal retinas and ultimately reaches unreal 

 brains. The next step takes it outside the cycle and gives 

 the opportunity of exposing the whole deception. Is 

 the brain disturbance translated into consciousness? 

 That will test whether the brain is real or unreal. There 

 is no question about consciousness being real or not; 

 consciousness is self-knowing and the epithet real adds 

 nothing to that. Of the infinite number of worlds 

 which are examples of what might be possible under the 



