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KIDD'S OWN JOURNAL. 



supposes the internal sense ; that if the posi- 

 tive laws of thought were not innate, there could 

 exist neither logic nor philosophy ; in fine, that all 

 the propensities and all the primitive faculties de- 

 pend on a determinate and peculiar organisation. 



SECTION III. 



ON THB CONDITIONS REQUIRED FOR THE MANI- 

 FESTATION OF MORAL QUALITIES AND 

 INTELLECTUAL FACULTIES. 



In the section preceding, I have stated our opi- 

 nion on the origin of _the instincts, the propensi- 

 ties, the talents ; in fine, on the origin of our 

 moral qualities and intellectual faculties. There 

 now presents a second question, which is like- 

 wise of the highest importance to the physiology 

 of the brain ; to wit : whether these qualities 

 and these faculties can, in this life, manifest 

 themselves independently of material conditions ; 

 or, whether they require for their exercise 

 certain organs, with which they are in im- 

 mediate relation. 



If our moral and intellectual forces can mani- 

 fest themselves independently of corporeal condi- 

 tions, we might in vain seek in the organisation 

 the apparatuses of the moral qualities and the in- 

 tellectual faculties. It would always be impossible 

 to found a doctrine on the functions of the brain 

 and its parts, or a physiology of the brain. Man, 

 considered as amoral and intellectual being, would 

 be placed beyond the sphere of the observer. If, 

 on the contrary, I can show that there exists an 

 essential relation between his moral and intellec- 

 tual forces and his organisation, it will follow, that 

 the researches to discover these material conditions 

 are the most important study for the true physiolo- 1 

 gist. If, again, I can show, as I shall do in the 

 second volume, that these material conditions are j 

 the brain and its parts, we shall then have a ! 

 glimpse of the possibility of creating a doctrine j 

 of the functions of the brain, a doctrine which 

 exhibits the organs, by means of which all our j 

 propensities.sentiments and faculties are manifested 



The Manifestation of Moral Qualities and 



Intellectual Faculties depends on 



material conditions. 



When I say that the exercise of our moral and [ 

 intellectual faculties depends on material condi- 1 

 tions, I do not mean that our faculties are the pro- 

 duct of organisation ; this would be to confound 

 conditions with efficient causes. I limit myself to 

 what can be submitted to our observation. Thus, 

 I consider our moral and intellectual faculties so far 

 only as they become phenomena to us by means of 

 the cerebral organs. The physiologist must never 

 trust himself beyond the material world, and must 

 neither affirm nor deny any thing but what can be 

 proved by experience. He must not direct his re- 

 searches to a spiritual substance alone, nor to this 

 inanimate body alone ; the living man, the result 

 of a vegetative life and an animal life, is his object. 

 Consequently, he must not enter into these me- 

 taphysical questions : What is the nature and the 

 essence of the faculties themselves ? Are they the 

 attributes of a spiritual substance, or the properties 

 of organised matter? In a word, he must not seek 



to explain the union of the soul and the body, nor 

 their reciprocal influence ; nor how the influence 

 takes place, whether by the immediate action of the 

 Deity, by an ethereal fluid, or by a divine emana- 

 tion. Whether souls are united to bodies sooner 

 or later ; whether they are endowed with different 

 qualities in each individual, or are entirely similar 

 in all ; whatever may be the decision of theologians 

 and metaphysicians on this subject, my principle, 

 that the manifestation of the moral qualities and 

 intellectual faculties can take place only by means 

 of organisation, rests immoveable. 



The reader knows already, although I shall not 

 prove it fully till the second volume, that the brain 

 is the exclusive organ of our moral qualities and 

 intellectual faculties. He will then be prepared 

 to find that most of my arguments to establish my 

 proposition, are relative to this grand and noble 

 nervous system. 



1 . The Moral Qualities and Intellectual Facul- 

 ties manifest themselves, increase, and diminish, 

 according as their organs are developed, increase 

 in strength, and are impaired. 



What takes place in the functions of an inferior 

 order and their organs, likewise takes place in the 

 functions and the organs of a higher order. Now, 

 I have shown in sections first, second, and fourth, 

 of the first volume of my large work, that the dif- 

 ferent nervous systems develop and perfect them- 

 selves at different periods. It is thus, for example, 

 that the nervous systems of the viscera of the ab- 

 domen and the chest are almost wholly formed, 

 while the brain seems, as yet, only a pulpy mass. 

 The olfactory nerve, and the nerve of taste, perfect 

 themselves sooner than the auditory and the optic : 

 we also see that the functions of taste and smell 

 acquire their perfection sooner than those of hear- 

 ing and sight. These phenomena especially take 

 place in those animals, which, when born, are deaf 

 and blind. The same progress is remarked in the 

 development of the brain. In new-born infants, 

 we hardly discover any trace of fibres in the ap- 

 paratuses which serve to strengthen and perfect 

 this organ. These fibres show themselves dis- 

 tinctly in the posterior and middle lobes sooner 

 than in the anterior. The fibrous structure of the 

 cerebellum becomes visible only by degrees, and it 

 is not till after several months that the anterior 

 and superior parts of the brain develop themselves 

 with a decided energy. The brain is formed and in- 

 creases gradually until it has attained its perfection, 

 and this perfection takes place only between twen- 

 ty and forty years of age. At this last period there 

 seems to be no sensible change for some years ; 

 but in proportion as we advance in age, the system 

 gradually lessens, the brain emaciates and dimin- 

 ishes in size, and its convolutions become less 

 compact. 



This successive and gradual order of development, 

 stationary state, and failure, is the cause, and 

 serves to explain, why, in the new-born infant, the 

 only functions are those of the senses of voluntary 

 motion — the expression of the want of nourishment, 

 and of obscure sensations of pleasure and pain, de- 

 sire and aversion , why all this takes place only to 

 an imperfect degree ; why the infant begins, by 

 degrees, to attend to external objects, to act on 

 them, to manifest determinate desires and propen- 



