MAMMALIA. 



J'21 



the future. The invertebrated animal which deposits 

 the egg in circumstances which appear to us to be 

 chosen with the greatest judgment and knowledge of 

 the future, has no experience of the past to guide her 

 in her operations. All animals of that class may be 

 considered as animals, that is they produce but once, 

 and when the labour of production is over they 

 speedily perish. They also pass through various 

 stages of being before they become sexed animals, 

 and some of them have their duration in that state 

 so brief, that they do not require to feed even once 

 before they have accomplished their purpose, and are 

 gathered to the dust. Under such circumstances it 

 is altogether impossible that they can have any ex- 

 perimental knowledge respecting what will become 

 of their progeny, or whether one substance or situa- 

 tion is more fit for its reception than another. There- 

 fore, though they do place their eggs in the best 

 situations, no sagacity can be attributed to them on 

 this account ; and we might as well allege that the 

 salifying principle and the base, which, when chemi- 

 cally combined, form a salt, have a previous know- 

 ledge of the nature of the salt which they form, as 

 that an insect which deposits her single brood of eggs 

 and dies has a knowledge of the future fate of those 



po-o-s 

 t ct s - 



The same principle applies to all animals, not ex- 

 cepting man, in so far as man possesses a material 

 body and is animal. This body has sensation and 

 instincts, as the bodies of other animals have, and as 

 the whole of the senses are perhaps more fully deve- 

 loped in the human body than in that of any other 

 animal, though there are various animals which excel 

 man in the acuteness of single senses, yet we can in 

 no instance take upon us to say that the body is pos- 

 sessed of any knowledge, or that it can recal the 

 past as a guide to the future. 



The difficulty of separating the portion of our 

 actions which is bodily or animal from that which is 

 mental renders this a very nice point in the physiology 

 of our own nature, and it is exceedingly difficult for 

 us to perform an analysis of so searching a nature, as 

 to enable us to carry the animal part to the study of 

 other animals wholly divested of the mental part. 

 But it' this is not done we spoil the whole by jumbling 

 together elements which in themselves have no natu- 

 ral connexion. We have already stated the main 

 ground of distinction ; but, because it is a very im- 

 portant one, and not generally stated in books which 

 treat of this subject, we shall repeat it, earnestly 

 pressing it on the attention of the reader : the ani- 

 mal principle, whether more or less developed, acts 

 upon matter by suspending for a time the common 

 laws of matter, and assuming to itself, contrary to 

 those laws, the substances which are necessary for 

 the original growth and the subsequent repair of the 

 organisation in which it displays itself. But while it 

 does this it has no knowledge of the matter which it 

 appropriates, or of the laws of matter which it over- 

 comes in this appropriation. It merely performs 

 certain functions, which, according to our knowledge 

 of the subject, are the evidences of its peculiar nature, 

 and it is capable of performing these only for a time. 

 This time is longer or shorter, according to the spe- 

 cies ; but we are acquainted with no animal which 

 can hold out against the common laws of nature for 

 an unlimited period of time. It appears to be a 

 general arrangement of the whole creation, that the 

 more general in every ca?e shall include and controul 



the more particular ; and though we cannot in all 

 cases, or correctly in any case, state the precise cir- 

 cumstances which limit the life of an animal to that 

 period which we know to be its ordinary duration, 

 yet as death, by natural decay and without the con- 

 tingency of disease, is the common lot of all animated 

 beings, if disease does not peviously stop their career, 

 we must conclude that this death is the result of 

 causes too general and too powerful for being over- 

 come by the energies of animal life. Hence, though 

 the animal is enabled to overcome and controul the 

 general laws of matter, and apply a certain quantity 

 of matter to its organisation, yet this is a finite power 

 and measurable by time; nor is it unworthy of re- 

 mark, that, in the same species of animal, an unnatu- 

 ral forcing or stimulating of the power of animal life 

 always abridges its duration ; while, on the other 

 hand, a uniform degree of exercise lengthens the life 

 of the animal. 



This shortening and lengthening of life by the 

 means we have stated is a perfectly general truth, to 

 which there is no exception ; but it is one the state- 

 ment of which requires a good deal of knowledge and 

 caution before we can pronounce with certainty con- 

 cerning it. We must know the whole of the func- 

 tions and actions of life, in order that we may be able 

 to ascertain that they are all affected equally, other- 

 wise the means which we apply in order to procure 

 longevity may actually have the contrary effect. 



In contradistinctiun to what has been stated as the 

 leading characteristic of animal life, that of acting 

 upon matter but not knowing it, the leading charac- 

 teristic of mind as it exists in man, and we know not 

 of its existence in any other being, is that it knows 

 matter but cannot directly act upon mutter. We 

 ought perhaps to exempt from this a certain mysleri- 

 ous reciprocity of action which takes place between 

 the mind and the body, in which they appear mutually 

 to influence each other, both in a pleasurable and in 

 a painful manner. But upon this part of the subject 

 we are unable to speak with much precision ; because, 

 though when we come to action in which matter ex- 

 ternal of the body is affected, or even part of the 

 body itself moved, we can always refer a portion of 

 such action to the body, yet in the commencement 

 of such action as this, namely, in that in which it is 

 induced or begun, it is impossible for us to separate 

 the bodily part from the mental. Thus, for instance,, 

 in the act of reading a book, the eye sees a succes- 

 sion of variously formed spots of black on a surface 

 of white paper, and the mind acquires a certain por- 

 tion of knowledge, different in kind and in value 

 according to the nature of the book, though the 

 markings on the paper, except in the order of their 

 arrangement, may be exactly the same, when the 

 information which the mind receives is of little or no- 

 value whatever, or even when it is valueless or per- 

 nicious, as when it is of the utmost importance. That 

 there are many mental operations intervening between 

 the bodily perception of the printed letters and the 

 mental understanding of the sense which those letters 

 convey, we have no reason to doubt ; but the succes- 

 sion of these operations is so quick that it is impossi- 

 ble for us to take note of them, or to feel any part of 

 the train, except the bodily beginning and the mental 

 ending. 



This by the way leads us to another very remark- 

 able distinction between the mental principle and the 

 principle of animal life, and that' is the total indepen- 



