visual impression, even if this be only an indifferent one, so that 

 the somewhat feeble psychological reaction of it now comes into 

 consciousness with much sharper outlines. And secondly, the final 

 impression will correspond with the one which the observer inarbi- 

 trarily expected beforehand from his notion of the regular repetition 

 of the primary impression. The symmetrical arrangement thus 

 appears to represent one of the numerous means, by which mental 

 action is facilitated and an economy of energy is obtained. However, 

 I have mentioned these views here only as an instigation to perhaps 

 better ones, -- not because I think they bring a final explanation 

 of this complicated matter. l ) 



4. In this connection it seems not out of place perhaps 

 to make some few remarks about the question, in how far we 

 can really speak of true "symmetry" with respect to the geome- 

 trical properties of objects observed in nature? For it is certainly 

 true that we attribute to every animal, to every flower or 

 leaf or crystal, a characteristic external form. Everyone of us 

 can at a glance tell what the difference is between an oak-leaf 

 and that of a poplar, or between the octahedral alum-crystal and 

 that of quartz. 



But detailed observation soon teaches us that two oak-leaves 

 or two poplar-leaves, two alum-, or two quartz-crystals, are never 

 absolutely identical ; and that, properly speaking, an undisturbed 

 and invariable regularity of form, as the result of an accurate 

 repetition of definite parts of the object, is never be met with. 

 Thus the one half of the oak-leaf appears never to be precisely 

 the same as the other half; the alum-crystal never has twelve 

 accurately equal angles, etc. Notwithstanding this variability, 

 however, we never hesitate in recognising a given leaf as being 

 that of an oak-tree, nor a given alum-crystal as being an octa- 

 hedron. The reason of this is, that as a consequence of our frequent 



1) Similar views on the aesthetic action of symmetrical arrangement have 

 also been brought forward and formulated by G. Heymans: Zeits. f. Psy- 

 chologic und Physiologic der Sinnesorgane, 11, p. 333, 335, 339, 340. (1896). 

 The question is here considered from the general point of view of the adaptation 

 of attention to subsequent observation, as a consequence of the psychological 

 preparedness for that coming impression, when its special nature is quali- 

 tatively and quantitatively on the same level with what was expected in 

 imagination. If this be the case, according to this author, a feeling of comfort 

 and delight will be produced, because of the easy assimilation of the real 

 occurrence to the analogous expectation already present in the mind. 



