CHAPTER XVIII 



SCIENTIFIC HYPOTHESIS RADIOACTIVE 



SUBSTANCES 



THE untrained mind, reliant on so-called facts and 

 distrustful of mere theory, inclines to think of truth 

 as fixed rather than progressive, static rather than 

 dynamic. It longs for certainty and repose, and has 

 little patience for any authority that does not claim 

 absolute infallibility .-[ Many a man of the world is 

 bewildered to find Newton's disciples building upon 

 or refuting the teachings of the master, or to learn 

 that Darwin's doctrine is itself subject to the univer- 

 sal law of change and development. Though in ethics 

 and religion the older order changes yielding place to 

 new, and the dispensation of an eye for an eye and 

 a tooth for a tooth finds its fulfilment and culmina- 

 tion in a dispensation of forbearance and non-resist- 

 ance of evil, still many look upon the overthrow of 

 any scientific theory not as a sign of vitality and ad- 

 vance, but as a symptom of the early dissolution or 

 at least of the bankruptcy of science. It is not sur- 

 prising, therefore, that the public regard the scientific 

 hypothesis with a kind of contempt ; for a hypothesis 

 (i>7ro^ecrt9, foundation, supposition) is necessarily 

 ephemeral. When disproved, it is shown to have been 

 a false supposition; when proved, it is no longer 

 hypothetic. 



Yet a page from the history of science should in- 

 dicate that hypotheses play a role in experimental 



