98 THE FOURTH DIMENSION. 



therefore, as we can locally fix the idea of a two-dimensional mate- 

 rial world, as little can we ever verify the notion of a four-dimen- 

 sional material existence. 



VI. 



EXAMINATION OF THE HYPOTHESIS CONCERNING THE EXISTENCE 

 OF FOUR-DIMENSIONAL SPIRITS. 



In connection with the belief that the visible world is contained 

 in a four-dimensioned space, Zflllner and his adherents further hold 

 that this higher space is inhabited by intelligent beings who can 

 act consciously and at will on the human beings who live in expe- 

 riential space. To invest this opinion with greater strength, Zollner 

 appealed to the fact that the greatest thinkers of antiquity and of 

 modern times were either wholly of this opinion or at least held 

 views from which his contentions might be immediately derived. 

 Plato's dialogue between Socrates and Glaukon in the seventh book 

 of the Republic, is evidence, says Zollner, that this greatest philos- 

 opher of antiquity possessed some presentiment of this extension of 

 the notion of space. Yet any one who has connectedly studied and 

 understood Plato's system of philosophy must concede that the so- 

 called "ideas" of the Platonic system denote something wholly dif- 

 ferent from what Zollner sees in them or pretends to see. Zollner 

 says that these Platonic ideas are spatial objects of more than three 

 dimensions and represent "real existence" in the same sense that 

 the material world, as contrasted with the images on the retina, rep- 

 resents it. Zollner similarly deals with the Kantian "thing-in-it- 

 self," which is also regarded as an object of higher dimensions. 



To show Kant in the light of a predecessor, Zollner quotes the 

 following passage from the former's "Traume eines Geistersehers, 

 erlautert durch Traume der Metaphysik " (1766, Collected Works, 

 Vol. VII. page 32 et seq.): "I confess that I am very much in- 

 "clined to assert the existence of immaterial beings in the world, 

 " and to rank my own soul as one of such a class. It appears, there 

 "is a spiritual essence existent which is intimately bound up with 

 "matter but which does not act on those forces of the elements by 

 " which the latter are connected, but upon some internal principle 



