3i6 APPENDIX. Chap. I. 



which Is undoubtedly of the metaphyfical kind, have net made the di- 

 ftindion betwixt Motion by Mind and Motion by Body, nor betwixt 

 the manner in which Mind moves Body, and that in which Body 

 moves Body ; and 1 am afraid they have not rightly made the capital 

 diftindion, betwixt Mind and Body, which is the foundation of all 



good philofophy. Even as to Motion by Body, which Sir Ifaac 



appears only to have confidcred, tliey have not diRinguiflied, as I 

 have obferved, betwixt Motion by Pulfion, and Motion by Trufion, 

 nor betwixt the two ways in which Motion may ceafe, viz. by exter- 

 nal obftrudion, or by the ceafing of the moving power to ad. And 

 there is another mod material diftindion in the fyftem of nature, 

 betwixt the fympathetic Motion of Bodies, and the Motion of the 

 one being the caufe of the Motion of the other. This fo material 

 diftindion they have negleded to make In the cafe of the tides, 

 and therefore have fuppofcd, I think, moft abfurdly, that the Mo- 

 tions of the moon are the caufe of the Motions of the fea ; not 

 knowing that, as the univerfeis a fyftem, and the moft perfed of all 

 fyftems, being the produdion of infinite wifdom and power, all the 

 Motions in it muft have a fympathy, more or lefs, with one ano- 

 ther ; and, therefore, that the faying of antient wifdom, which I 

 have elfewhere quoted, ' That all things in the univerfe fympathife 

 ' with one another,' Ihows a moft profound knowledge of the fyftem 

 of Nature. 



If I might prcfume further to advife thefe gentlemen, I would re- 

 commend to them, if they will continue ftill to fpeculate upon a fub- 

 jed fo different from geom.etry and mechanics, as the origin and 

 continuation of Motion, to ftudy a little the philofophy of Mind, 

 and to follow the example of their mafter Sir Ifaac, who at firft ap- 

 pears to have had no other idea of the origin of Motion, but that 

 which falls under the fenfes, I mean bodily impulfe : Some years after 

 thisj it appears from his correfpondence with DrBentley, that he began 



to 



