Postulates of Evolution. 123. 



very business of science to do so. Nothing is to be 

 deemed inexplicable by natural law, unless there be 

 good reason to judge that such explanation is not 

 possible. Even when for a time baffled, it is the part 

 of science to return again and again to the search, in 

 hope of accomplishing, by patient toil, the seemingly 

 impossible achievement. But it is not to be tolerated 

 that there should be buried under the pretence of 

 solution, difficulties that remain still unsolved. Nor 

 are working hypotheses to be raised to the rank of 

 established truths. There should be as much keen- 

 sightedness in recognizing the want of completeness 

 in proof, as there is in noting facts that seem to 

 support a theory. The adverse facts are to be re- 

 corded with as much care as those that are favour- 

 able. The one class of instances is as precious to true 

 science as the other. 



When it is asserted that all the causes of all that 

 may be known are included within the cosmos, the 

 proposition is ambiguous till we have first fixed the 

 limits of the cosmos as conceived in thought. If the 

 cosmos be infinite, embracing all existences God, the 

 soul, and the world it includes of necessity all causes. 

 The proposition, read in that sense, is an identical 

 proposition it amounts to affirming that all things 

 include all things. It does not in the least degree 

 advance our knowledge ; for what science has to do 

 is to trace the relations among phenomena within 

 that infinite, in their Mo- ordination and succession ; 



