160 



MAMMALIA. 



pointof view. The universality, so to speak of the human 

 mechanism, necessarily renders man less efficient, in 

 proportion to his general muscular strength, for some 

 one particular kind of natural action, than any one ani- 

 mal with which a comparison can be instituted. The 

 same holds good in those manual and mechanical 

 operations which man learns from experience, as from 

 the exercise of his mental faculties. There is perfect 

 truth in the proverb " Jack of all trades and master 

 of none," and this applies to every mechanical trade, 

 whether the manipulation which it requires be simple 

 or complex. The more simple that it is, however, 

 the greater the practical advantage, because the same 

 practice necessarily gives greater dexterity and ex- 

 pertness. If, for example, it is a single and simple 

 mechanical operation, which does not admit of two 

 individuals being employed at it, then the handicraft 

 labourer may be said to work to the greatest possible 

 advantage to which he can work ; and were it possible 

 to reduce all the manual operations in the arts to 

 this state of the ultimate division of labour, the whole 

 of events would derive the greatest possible advan- 

 tage from the least possible exertion. 



This advantage of the division of labour is not 

 confined to merely manual operations, for it applies 

 equally to every kind of doing, however philosophical 

 the principle may be upon which that doing proceeds. 

 This will be readily understood, if it is borne in mind 

 that we derive our original knowledge of every pro- 

 perty of material substance by the exercise of bodily 

 sensation alone. What use we may make of this 

 observation afterwards is quite a different matter, and 

 has not necessarily anything to do with the acuteness 

 of the bodily sense. It is here that the mental part 

 of our nature takes up the subject, and by comparing 

 the results of observations after they have become 

 mental perceptions, discovers their relations, and the 

 purposes or uses to which those relations may be 

 applied. When we come to the application again, 

 we are thrown completely upon the bodily sense and 

 the muscular exertions of the body, which are neces- 

 sary as consequences of the information of the senses 

 as to the nature of the materials immediately under 

 our hands. In this case, therefore, the same as in a 

 single case of sensation, mental perception, and con- 

 sequent action, it is only the middle part, or the 

 vinculum, by which the other two are as it were tied 

 together in the sequence, which is mental or intellec- 

 tual, and peculiar to man and all the animated creatures 

 of which we have any direct experience. Take away 

 this, and leave only the sensation and the action, arid 

 man would be placed exactly on a level with the 

 other animals ; that is, both his sensation and his 

 action would be more feeble and imperfect upon 

 every single subject, in proportion to the greater 

 number and variety to which they were turned. 



The parallel between man and the other animals 

 in respect to increase of power from diminution of 

 range, goes even a good deal further than this ; for 

 it reaches the directing of others, as well as the prac- 

 tical management of our own affairs ; and in propor- 

 tion as the ranee in either of those cases is more 

 limited, the efficiency with equal exertion is increased 

 not only in respect of the individual subject of atten- 

 tion, but in respect of the total practical value of the 

 exertion. It is natural, and indeed necessary, to sup- 

 pose that this should be the case ; for, in so far as 

 observation imwarped by any hypothesis or theory 

 goes, we find all animals proceed upon the same 



principle, varied almost without end in the different 

 species, but still radically and substantially the same. 

 Man, considered as animal, is produced, grows, is 

 nourished, and dies, exactly upon the same principle 

 as the other mammalia ; and in proportion as they 

 resemble him in their alimentary system, they are 

 nourished the belter by the same food, injured more 

 certainly by the same changes, and killed more cer- 

 tainly by the same poisons. So that, in every point 

 of view in which man considered merely as an uniimtl 

 can be placed, he follows that general law which is 

 common to all animals, and his physical advantages and 

 disadvantages depend upon circumstances precisely 

 similar. This perfect coincidence, in general prin- 

 ciples, between ourselves and the other animals, in the 

 merely animal part of our nature, is one of the most 

 important applications that can be made of the natu- 

 ral history of animals, because it enables us to bring 

 our mental powers to bear upon them, and to profit, 

 so to speak, by their experience as well as by om 

 own. " Go to the beasts and they shall instruct, to 

 the fowls of heaven and they shall teach knowledge," 

 says an authority which cannot be doubted, and we 

 have practical demonstration of it in the propei 

 analysis of the case. This analysis consists in a care- 

 ful separation of all that portion of our progress from 

 sensation to action which is animal, from that which 

 is intellectual, and the general conclusion taught to 

 us by the mammalia, which, as they resemble us the 

 most, are our fittest instructors ; and the conclusion 

 we arrive at is this that to this purely animal part 

 the principle of the division of labour cannot be too 

 constantly or too rigidly applied,and that the perfection 

 of the profitable use of this part of our compound nature 

 consists in dividing it down to the individual sensation 

 and the individual act. It is true that this is a dctrrpe 

 of perfection which cannot be arrived at, or even very 

 closely approximated, by all the members of any com- 

 munity, or even by any single individual ; but oui 

 imperfections do not invalidate the principle, and so 

 the further that we can carry it in every case, the 

 greater is our reward in proportion to the duration 

 and severity of our labour. 



But we must be on our guard against applying this 

 conclusion to what we arrive at by the most legitimate 

 philosophical means, respecting the one part of oui 

 compound nature, to the other part of it. The ex- 

 amination of one of the parts of this compound nature 

 of man would therefore be not only imperfect, but il 

 would be apt, and even certain, to mislead those who 

 are not conversant with such inquiries, if it were not 

 accompanied by some notice of at least the leading 

 principle of the other part. Now though, according 

 to the foundations cf our judgment of matter, we have 

 nothing but negative perceptions and consequently 

 negative definitions of mind, those negatives enable 

 us, though not to say what it is in itself, yet to say in 

 what it differs from matter. The essential and inse- 

 parable property of matter which belongs to it in all 

 its forms and in all their modifications is gravitation, 

 or a certain tendency the action of which cannot be 

 restrained, or turned into a different direction from 

 the straight line joining the centres of gravity in two 

 pieces of matter, except by the operation of some 

 force. The quantity of this operation is all that is 

 resolvable into two elements time and force, of which, 

 when they can be stated in numbers, the product is 

 the expression for the energy of the force or power ; 

 and, as in the case of the same force or power, this 



