when separatedfrom the body. 309

object to another action. We are indeed so ac-customed to feel difficulty in action, when weact by the body, that if an action costs us notrouble in performing it, or produces no sen-sible change in matter, we lose the notion of°Ur being active, and the dlJlinSlion we haveformed to ourselves between action and inaSti-When we move a limb of the body spon-taneously, it is confessedly action; motion isa sensible change: but it is no less action tobold the arm straight out, than to put it at firstln to that posture, which we may be sensibleof, because we soon find ourselves unable toContinue it thus (J >); and that is no sign of in-GSiion. And agreeable to this, a close atten-tion of thought to the fame thing, is morefatiguing than frequent changing; there be-ing, as was said above, a relief and pleasurevariety of objects. So far is it from be-

(p)Hoc \tremorem induct, ob defediumsuccispirituosi\confirmatur ex co, quod viri alioquin rohujii, pondus pro-prii brachii extenji sujlinere non pojfunt , continuata aSlione[here it is called action] per horam integrants absquetre-ftore. SJuia nempe , oh continuatam effusion cm ex iifdcrnKervis, succiJpintuoJi dijjipantur, et deficiunt , et prainde ,interruptis vicibus , 43 ? minutis Jlillicidm cxpritni pojfunt .[In which intervals the arm must yield and sink down2 little.] Borell. de mot. animal. Part. 2. Prop. 216.

X 3 ing