PHILOSOPHY OF NATURE LEIBNITZ'S IDEAS. 33 



reacts against our own force as strongly as our own force 

 acts to surmount it. Whether this resistance makes itself 

 known directly, in the immediate apperception of the 

 effort put forth by the I outside of itself, or whether the 

 mind clothes it in some other conception, that force is de- 

 finitively conceived in the same way as the I is conceived, 

 as a pure and absolute category, with no appreciable 

 shape. This active force, Leibnitz holds, differs from bare 

 force of which the schools talk, in this respect, that the 

 entire power, or faculty, of the scholastics, is only the im- 

 minent possibility of action, which still requires, before 

 passing into action, an impulse from without ; but the active 

 force we speak of intends a kind of actuality which holds 

 a middle place between the power to act and the act itself, 

 and takes effect as soon as the obstacle is removed. As a 

 clear illustration, take the instance of a weight stretching 

 the cord that holds it up, or of a strung bow. Or, again, 

 we cannot possibly describe in what respect a body in 

 motion, at each one of the points it successively occupies, 

 differs from a body at rest, unless we add that at each of 

 those points it tends to go onward. 



The mind thus takes in, by the method of metaphysical 

 abstraction, the primitive capacities of action, the actuali- 

 ties, the powers that give to matter its dynamic charac- 

 teristics. Leibnitz considers these capacities, to which he 

 also gives the name of monads^ as real and absolute prin- 

 ciples, the sum of which in Nature is always the same, 

 while the quantity of motion in Nature is variable. Every 

 sort of phenomenon resolves itself into these substantial 

 unities, the number of which is infinite, and which are the 

 only mode we have of conceiving bodies and souls. Atoms 

 of matter are contrary to reason apart from their being 

 themselves made up of parts because, however invin- 

 cible the attachment of one part to another may be, that 

 does not alter the fact of their diversity. There exist only 



