THE MEANING OF NATURE 257 



is very difficult to determine just what is the good for them. 

 But it is sometimes a different matter if we look at such things 

 in the general scheme of the universe. Then their observed 

 tendencies to certain acts very often appear as contributing to 

 the order and good of the whole, they are seen within the 

 framework of the general intention of universal nature. ~° This 

 was the case even of the heavenly bodies. One could say that 

 they did not tend to movement as to a perfection for them, but 

 that such movement was intended by nature for the generation 

 of rational beings. By such movement they were constituted 

 in their given role of causes of alteration in the universe. The 

 tendency known as " gravity " can also be seen as contributing 

 to a general order. Even the tendency of water to be warmed, 

 sometimes given by St. Thomas as a simple example of an 

 intrinsic passive principle of natural movement, could be seen 

 as contributing to the good of the whole. 



To complete the general picture, however, the passive 

 potency should be seen in relation not only to its act, as we 

 have been viewing it, but also to the agent which confers the 

 act. In his commentary on Book VII of the Metaphydcs,^^ St. 

 Thomas explains natural potencies in terms of forms and 

 agents: " The difference between the matter of natural things 

 and the matter of artificial things is that in the matter of 

 natural things there is a natural aptitude for the form and it 

 can be reduced to act by a natural agent; this does not happen 

 in the matter of artificial things." (Italics mine.) Indeed, the 

 universe may be considered as a whole composed of parts so 

 interrelated that they are acting upon one another or being 

 acted upon by one another, so that everything according to its 

 particular nature is related to something else or to many things 

 as either patient or agent, or both, though not of course in the 

 same respect — and all for the good of the universe as a whole. 

 Thus, to use a simple example, water would be related to both 

 fire and the north wind as passive, fire and the north wind to 



" Nature taken as the whole system of interrelated individual natures. 

 " Lectio 8, n. 1442Z. 



