240 On the Vital Principle. 



the caufe of palfy almoft always refides in the 

 brain, this faft appears equally inexplicable, on 

 the opinion of a diftina living principle, or of 

 a nervous energy independent of the brain. 



5 When nerves are regenerated, after being 

 cut 'through, fenfation and voluntary motion 

 are not always reftored to the parts beneath the 

 divifion : the reftoration was never made in 

 Dr Monro's experiments*. But on the fup- 

 pofition of a diftina nervous power, the nerve, 

 after its re-union, ought to refume all its offices. 

 6 Dr Whytt afferts, that when the ipinal 

 n^arrow of a frog is deftroyed, after decollation, 

 no contraftion can be excited in the Innbs by 

 cutting or tearing the mufclest. 



While fo many doubts occur refpeding the 

 proof of a vital principle, and while the fuppofi- 

 tion includes fo many difficulties, in us own 

 nature, it is allowable to fufpend our judgment 

 on the fubjecl, till more convincing proofs ot 

 its eociftence (hall appear, than have as yet been 

 offered to the public. 



At prefent, it is evident that we gain nothing 

 by admitting the fuppofition, as no diftinft 

 account is given of the nature or produftion ot 

 this principle, and as an inveftigation of fads 

 feems to lead us back to the brain, as the fource 

 uf fenhbility and irritability. 



* Obkrvations, p. ^7. 



t Obf. on Irritab. and Senfib. p. 2S4. 



