CONCEPTS OF &quot; REASON &quot; AND CA USE &quot; 67 



activity. * When we speak of Physical Nature, or the Order of 

 Nature, or the Course of Nature, or External or Visible Nature, we 

 use the term &quot; Nature,&quot; in a collective sense, to signify the sum- 

 total of all the created agencies that make up the visible (i.e. 

 sensible, perceptible) material universe. 



Hence, the extension of the concept of purpose from the do 

 main of rational or human agents to the animal, vegetable, and 

 inorganic kingdoms of nature, by Aristotelean and Scholastic 

 philosophers, is no mere &amp;gt; verbal metaphor. There is a true and 

 proper sense, as these philosophers contend, in which all created 

 agencies act in fulfilment of purpose, in which &quot;ALL agents act 

 for an end &quot; : &quot; OMNE agens agit propter finem &quot;. 



The conviction is gradually forced in upon us by our experi 

 ence of natural phenomena, that every agency in nature must 

 have some fixed, intrinsic principle of activity, in virtue of which 

 it acts uniformly, and concurs with other physical agencies, not 

 capriciously or indifferently, but along certain prearranged and 

 predetermined lines ; so that &quot; exceptions &quot; to this uniformity 

 must be due in reality to the influence of some unknown natural 

 causes, or, possibly, to the intervention of the First Cause. Here, 

 at all events, is the great fact we gather from sense experience : 

 that very complex combinations of numerous natural agents re 

 peatedly concur to produce uniform series of effects. Of this 

 great fact there can apparently be one, and only one, rational in 

 terpretation : that which conceives the proximate causes of such 

 uniform series of phenomena as endowed each with a fixed natural 

 inclination or tendency to act steadily and consistently along de 

 finite lines, as having each an internal law which dominates it, 

 and in conformity with which it will act always and everywhere. 

 This innate, stable tendency is what the mind grasps when it 

 apprehends the law of the Uniformity of Nature. The great fact of 

 experience revealed in the regular, constant, harmonious concurrence 

 of numerous and varied forces and agencies to produce uniform series 

 of results, finds its sufficient reason and explanation only in a 



1 The Essence of a thing (&quot; Essentia &quot; or &quot; Quidditas &quot;) is that which makes 

 the thing what it is (&quot; id quo res est id quod est &quot; : the answer to the question &quot; Quid est 

 ilia res } &quot;). The Nature (&quot; Natura &quot;) is the essence itself looked on as the directive 

 principle of the thing s activities (the &quot; principium operationis &quot;). It was conceived 

 by the Scholastics as the impression of a divine directive plan or design on the inner 

 constitution of the created agency : &quot;Stabilis inclinatio vel appetitus finis, rebus a 

 Deo inditus&quot; or again, &quot; Ars quaedam Divina indita rebus, per quam ad fines pro- 

 prios non solum ducuntur sed quodammodo vadunt.&quot; St. Thomas, Q(^. DD. De 

 Veritatc, Q. xxii, a. i. 



5* 



