LIMITS OF INVESTIGATION. 15 



mensurable with scientific truths. We will therefore 

 abide by the words of Goethe : 



\Vhoso has art and science found, 



Religion, too, has he; 

 Who has nor art nor science found, 



His should religion be.* 



And now, having provisionally averted uncalled-for 

 objections and conflicts with ambiguous ideas, we may 

 quietly consider the limits of natural science. Let us 

 first pause at the address delivered with general approval 

 by the physiologist Dubois-Reymond, at the fiftieth 

 assembly of German Naturalists and Physicians. He 

 made reference to a passage in the classical works of 

 Laplace, in the Introduction to the Theory of Science, 

 which we cannot refrain from quoting in full. The 

 author of the "Mechanism of the Heavens," says: "Pre- 

 sent events are connected with the events of the past by 

 a link resting on the obvious principle that a thing cannot 

 begin to exist without a cause which produces it. This 

 maxim, known by the name of the Principle of Sufficient 

 Cause, extends likewise to events with which it is not 

 supposed to come in contact. Even the freest will can- 

 not evoke them without a determining impulse." "We 

 must, therefore, regard the present condition of the uni- 

 verse as the consequence of its former, and the cause 

 of its future, condition. A mind, for a given moment 

 acquainted with all the forces which animate Nature, 

 and the reciprocal relations of the entities of which it is 



* Wer Wissenschafft und Kunst besitat. 



Hat auch Religion ; 

 Wer jene Leiden nicht besiizt, 

 Der habe Religion. 



