308 RECENT PROGRESS OF THE THEORY OF VISION. 



or logical conclusion, is the culminating point of the 

 conscious operations of the mind. But the judgments 

 which play so great a part in the perceptions we derive 

 from our senses cannot be expressed in the ordinary 

 form of logically analysed conclusions, and it is neces- 

 sary to deviate somewhat from the beaten paths of psy- 

 chological analysis in order to convince ourselves that 

 we really have here the same kind of mental operation 

 as that involved in conclusions usually recognised as 

 such. There appears to me to be in reality only a super- 

 ficial difference between the 'conclusions' of logicians 

 and those inductive conclusions of which we recognise the 

 result in the conceptions we gain of the outer world 

 through our sensations. The difference chiefly depends 

 upon the former conclusions being capable of expression 

 in words, while the latter are not ; because, instead of 

 words, they only deal with sensations and the memory 

 of sensations. Indeed, it is just the impossibility of 

 describing sensations, whether actual or remembered, in 

 words, which makes it so difficult to discuss this depart- 

 ment of psychology at all. 



Beside the knowledge which has to do with Notions, 

 and is, therefore, capable of expression in words, there is 

 another department of our mental operations, which may 

 be described as knowledge of the relations of thoso 

 impressions on the senses which are not capable of direct 

 verbal expression. For instance, when we say that we 

 ' know ' 1 a man, a road, a fruit, a perfume, we mean that 

 we have seen, or tasted, or smelt, these objects. We 

 keep the sensible impression fast in our memory, and we 

 shall recognise it again when it is repeated, but we 



1 In German this kind of knowledge is expressed by the verb Jcennen 

 (cognoscere, connaitre), to be acquainted with, while wissen (scire, savoir) 

 means to be aware of. The former kind of knowledge is only applicable to 

 objects directly cognisable by the senses, whereas the latter applies to 

 notions or conceptions which can be ^ormally stated as propositions. TR. 



