Ancient and Mediaeval Science 33 



worthless, dangerous and subversive. Even so we should not be too 

 severe in judging those aberrations, for we have not yet succeeded in 

 overcoming them and but for the control of scientific societies and acade- 

 mies, the incessant criticism coming from the scientific press and the 

 university chairs, our own civilization would soon be overrun and smoth- 

 ered by superstitions and lies.^^ 



Our judgment of mediaeval science in general must always be tem- 

 pered by the considerations which have just been offered and by due and 

 profound humility. We may be great scientists (I mean, we modem 

 men), but we are also great barbarians. We know, or seem to know, 

 everything, except the essential. We have thrown religion out of doors 

 but allowed superstitions, prejudices and lies to come in through the 

 windows. We drum our chests in the best gorilla fashion saying (or 

 thinking) "We can do this . . . we can do that . . . yea, we can even 

 blow the world to smithereens," but what of it? Does that prove that 

 we are civilized? Material power can be as dangerous as it is useful; 

 it all depends on the men using it and on their manner of using it. 

 Good or evil are in ourselves; material power does not create it but can 

 multiply it indefinitely. 



To return to the Middle Ages it was a long period not of darkness 

 and sterility but of gestation. To call it sterile would be just as foolish 

 as to call a pregnant woman, sterile. Wait and see! It takes nine 

 months of patience in one case and nine centuries in another but time 

 does not matter. Mediaeval developments were undoubtedly slow as 

 compared with our own tempo, but are we not going too fast? Our 

 speed is not necessarily a good thing, nor very admirable; it is largely 

 due to accumulated inertia. It would require unusual wisdom to brake 

 it, and we are short on wisdom. 



The essential weakness of mediaeval thought was due to the lack 

 of understanding of the experimental method and of the experimental 

 point of view. Once that "open sesame" had been found, discoveries 

 followed one another, almost automatically in some cases, with increas- 

 ing speed. Modern science is the fruit of three centuries of that method. 

 Its early development was exceedingly slow. Even the Greeks, so full 

 of genius, had failed to discover it, though some of them had applied 

 it in particular cases.^^ A few Muslim, Christian and Jewish scientists 

 of the Middle Ages applied it too, but with the exception of Roger 

 Bacon (XIII-2), nobody formulated it nor recognized its generality and 

 its astounding potency .^^ 



** See review of a new edition of Ptolemy's Tetrabiblos for practical use, 

 Chicago 1936 (Isis, 35, 181). 



^ Ptolemy ( II-l ) in his study of refraction, Galen ( II-2 ) in his experiments 

 to determine the function of the kidneys, and of the cerebrum and spinal chord at 

 difiFerent levels. 



^ Roger Bacon's formulation constitutes the sixth part ( out of seven ) of the 

 Opus majus written in 1268. It can easily be read in Robert Belle Burke's trans- 

 lation (p. 583-634, Philadelphia 1928; Isis, 11, 138-41). The letter on the magnet 



