50 CEREBRAL FORCES. [i. 



of external sensations. Some may, however, surpass the latter, if 

 compounded of many external sensations (53). The stronger the 

 imaginations, the more effective are their material ideas (26). 



68. That which is wanting in the material ideas of the 

 imaginations, so that they do not form the perfect material 

 ideas of external sensations, is, the external impression trans- 

 mitted along the nerves to the brain ; which also renders the 

 material ideas more perfect, and consequently, the conceptions 

 richer in sub-impressions [merkmale] than those which the 

 mind can produce without it (53). 



69. If material ideas act as animal-sentient forces of the 

 brain (6) in the animal economy, and excite animal actions, the 

 actions excited by material ideas of imaginations must partly 

 accord with those of antecedent external sensations {67, 66). 



70. Since dreams are often imaginations of the sleeping 

 state (sensational conceptions), which in somnambulism, and 

 during the waking state in insanity, become so distinct that 

 they cannot be distinguished from external sensations, the 

 rules stated previously (67 — 69), with reference to imaginations, 

 are applicable to all these. When the mind spontaneously 

 combines many imaginations, it invents poetically [dichtet sie] . 

 (Baumgarten's ^ Metaphysics,^ § 438.) All that has been 

 stated as to imaginations and their material ideas, is applicable 

 also to fictions (Erdichtungen). 



71. All conceptions are connected with their proper material 

 ideas (25). But for the mind to know regarding the same 

 conception returning at different times, that the last is the 

 same as the first, a renewed conception is requisite, and it 

 remembers, or an act of memory takes place; but it is not 

 necessary to this end, that the first should be continuous with 

 the last. So little, indeed, is this continuity necessary, that 

 a long period may elapse before the renewal, without there 

 being a trace of the conception in the mind, and still when re- 

 developed, the mind knows that it is the same as the previously 

 existing conception. It is equally unnecessary for the material 

 idea of a conception thus remembered to have a continuous 

 impression on the brain, or to leave traces behind it, of which 

 the mind makes use, so as to recognise the renewed conception 

 as having previously been present to it. Each recognition of 

 a conception is much rather an operation of the mind [con- 



