2 ADDRESS OP 



Nature, that it is necessary to approach my idea from more than 

 one standpoint, and to illustrate it in more than one way. 



We all know that the history of the Caucasian race, during the 

 last three centuries, has been marked by a kind of intellectual 

 development so entirely without precedent that some might call 

 it miraculous ; in fact, by such a development of the understanding 

 of the course of nature as has revolutionized human society in 

 many of its phases. You also know that thi^s development has 

 been marked by frequent collisions of opinion between the inves- 

 tigators of the material manifestations of nature on the one side 

 (if I may be allowed to use the expression), and philosophers and 

 theologians on the other, respecting the true theory of the course 

 of nature. My desire in entering this field is to act the part of 

 the peacemaker rather than that of a combatant, not sustaining 

 any other propositions than those which are actually believed in 

 by the large majority of educated men at the present time ; but 

 the confusion of thought on this subject, to which I have just 

 alluded, is so great that, although I may combat no opinions 

 actually held, it may be necessary to greatly modify their applica- 

 tion, and to criticise the forms in which they have found expres- 

 sion. 



The key-note of my discourse is found in a proposition which is 

 fundamental in the history of modern science, and without a clear 

 understanding of which everything I say may be entirely misun- 

 derstood. This proposition is, that science concerns itself only 

 with phenomena and the relations which connect them, and does 

 not take account of any questions which do not in some way admit 

 of being brought to the test of observation. The only universe it 

 knows is that made known by the telescope, the microscope, and 

 other appliances of observation. That this is the whole universe 

 we should all be very sorry to suppose, and none more so than he 

 who has the honor to address you. But, should I pretend to a , 

 scientific knowledge of what lies behind this visible frame, I should 

 be acting the part of the rash speculator rather than of the cau- 

 tious thinker. Only into a single field of thought do I dare to 

 venture. When we trace the efforts of men to penetrate the 

 secrets of nature, we find them clearly divisible into two classes : 

 philosophic speculation, and scientific investigation. We find the 

 objects of thought equally divisible into two classes : phenomena 

 and their hidden causes, those unknowable entities out of which 



