December 19, 1913] 



SCIENCE 



867 



This is merely one example of the usual 

 dependence of the ancients on the authority 

 of abstract reason. By this means they 

 sought absolute certainty in scientific as 

 well as in mathematical and philosophical 

 thought. A brief account of their general 

 point of view in regard to this matter will 

 serve to connect the two topics which I have 

 asked you to associate together this evening ; 

 for it is in the ancient time that the two 

 methods are most closely related. 



It is convenient to speak of the position 

 of Plato. This philosopher refers, with a 

 touch of contempt, to one who gives hia life 

 to the investigation of nature, feeling that 

 such a person was concerned with the visi- 

 ble universe alone and was immersed in its 

 phenomena. These, whether past or pres- 

 ent or to come, admit of no stability and 

 therefore of no certainty. ' ' These things, ' ' 

 he says, "have no absolute first principle 

 and can never be the objects of reason and 

 pure science." Plato believed that the 

 senses are deceptive and could never lead 

 to the discovery of truth. The only way to 

 develop science was to look within and find 

 there the fundamental principles on which 

 it should be based; and then to develop 

 logically the consequences of these prin- 

 ciples. 



But I shall not take up your time with 

 an analysis of these old opinions, however 

 much they may have influenced or retarded 

 science in times past. Neither shall I pause 

 to indicate how the old Greek science, such 

 as it was, came into a place of authority, 

 dominating the thought of many genera- 

 tions and giving rise to a fearful intellec- 

 tual stagnation. I prefer to come to the 

 time when the development of scientific 

 method began to recover men from their 

 stupor and to kindle a new intellectual 

 light and fervor. 



Let me direct your attention to the 

 Italian philosopher Bernardino Telesio 



(1509-1588) as the great figure who marks 

 the period of transition from authority and 

 reason to experiment and individual re- 

 sponsibility. He was the forerunner of all 

 subsequent empiricism, scientific and philo- 

 sophical, sowing the seeds from which 

 sprang the scientific methods of Campanello 

 and Bruno, of Francis Bacon and Descartes 

 and the scientists of our day. He aban- 

 doned completely the purely intellectual 

 sphere of the ancient Greeks and other 

 thinkers prior to his time and proposed an 

 inquiry into the data given by the senses. 

 He held that from these data all true 

 knowledge really comes. 



The work of Telesio, therefore, marks the 

 fundamental revolution in scientific thought 

 by which we pass over from the ancient to 

 the modern methods. He was successful in 

 showing that from Aristotle the appeal lay 

 to nature; and he made possible the day 

 when men would no longer treat the ipse 

 dixit of the Stagirite philosopher as the 

 final authority in matters of science. 



It is true that Telesio had been preceded 

 almost three centuries by Roger Bacon 

 (1214?-1294?), a modern thinker in the 

 middle ages, whose conceptions of science 

 were more just and clear than those at a 

 date four centuries after his birth. But 

 this Bacon was a man born out of time, too 

 far in advance of his age to be appreciated 

 by it; and consequently he had but little 

 influence on the growth of scientific method. 

 The balance has now been restored in his 

 favor, so far as the judgment of historians 

 is concerned ; but that leaves untouched the 

 facts of effective scientific progress. 



Telesio had several followers, or perhaps 

 we should say fellow pioneers, in the same 

 field. Among these Francis Bacon probably 

 stands out as the most prominent of all. He 

 said of himself that he "rang the bell 

 which called the wits together." But his 

 contributions to the stock of actual scien- 



