INSTINCT, SENSATION, AND INTELLIOENeE. 



243 



whole of this important change, this entire reproduction of the material sys- 

 tem, though occurring in sentient and even in intelHgent organs, occurs at 

 the same time without any kind of feeling or consciousness in the individual, 

 or the organs that constitute the individual. 



This very curious fact is still more obvious in the generation of new 

 matfer of every kind,— muscular, glandular, bony, and even nervous, upon 

 the death of a considerable portion of an organ in consequence of external 

 injury or other violence. The nice and admirable law by which the dead 

 substance is carried off, and its place supplied by the gradual reproduction 

 of fresh matter of the very same nature and properties, 1 have already ex- 

 plained.* In the separation of the dead from the living parts, there is 

 generally, though not always, some degree of pain, from the increased local 

 action that takes place, and more especially from the tension given to the 

 skin by the secretion of sound and healthy pus, in order to affect its burst- 

 ing ; but in the actual generation of the new material that is to fill up the 

 cavity, and supply the place of what is lost, there is no pain or sensation 

 whatever in a healthy process ; while, as I have likewise already observed, 

 the pointing of the abscess, like the pointing of the seeds of peas, or beans, 

 in what direction soever they are sown, will be uniformly towards the sur- 

 face,! whatever be the obstacles that must be overcome in order to reach it. 



The generation of life, then, no more necessarily demands or implies the 

 existence of sensation, than attachment to life, or a self preserving princi- 

 ple : it may be combined with it, but it may also exist separately or without 

 it. Monro, indeed, has distinctly proved by experiment, that the limb of a 

 frog can live and be nourished, and its wounds healed, without any nerve 

 whatever, and consequently without any source or known possibility of 

 sensation. 



Let us apply this reasoning, which I admit is thus far drawn from indi- 

 vidual parts of the system alone, to a regeneration or reproduction of the 

 entire system. 



The lungs or gills of an animal are precisely analogous to the leaves of a 

 plant. All these, as I have already observed, are perpetually changing by 

 a nicely balanced alternation of decay and reproduction. In animals and 

 ever-green plants this change is so gradual as to elude all notice. In de- 

 ciduous plants, on the contrary, it is sudden and obvious to every one ; yet 

 the same instinctive power that produces the one change, produces also 

 the other ; and as in the former case, we have a perfect consciousness that 

 the effect takes place without any sensation or intelligence, no man will be 

 so extravagant as to maintain that there is any sensation or inteUigence 

 concerned in the latter. But the very same process that produces the 

 leaves or shoots of plants, produces also their buds ; the vegetable vessels 

 are the same ; there is no new principle employed, but merely an adapta- 

 tion of the one common principle of instinct or the law of simple life, to 

 the production of a different effect ; for the very same eye may, by too much 

 or too little pruning of the wood, be converted into a shoot or into a bud. 

 The buds of plants, however, are their proper offspring ; and, in many cases, 

 as perfectly so, as their seedlings, or those reared from seeds. In other in- 

 stances we find a progeny equally perfect produced by a separation of bulbs 

 or roots, or by radicals shooting out from creeping joints, as in the straw- 

 berry. In all which it would be absurd, even if plants were possessed of a 



* Series J. Lect. XTV. 



t Series IT. Lect. IV. 



