THE ENGLISH PRECURSORS OF NEWTON. 78 q 



other leading men of the time. Thus, in Hooke's apprehension, the 

 raison d'etre of an hypothesis was not so much to suggest a physical 

 connection of facts as to provide a convenient classification of experi- 

 ments, and its most essential quality that it should be plausible, not 

 that it should be true. 



His judgment was besides warped, even more than that of most 

 men, by that intellectual egotism which, if it sometimes acts as a spur 

 to progress, more often performs the office of a drag. His self-love 

 blinded him to the real merits of his competitors. His own specula- 

 tions loomed so large before him as to exclude from his field of view 

 those of every other. Newton acknowledged that, if he saw farther 

 than most men, it was "by standing on the shoulders of giants." 

 Hooke thought his own mental statui'e sufficient to entitle him to re- 

 ject such extraneous aids. He accordingly set aside without hesitation 

 Newton's discovery, offering his criticisms, not indeed discourteously, 

 but with a certain air of superiority which not a little galled his sen- 

 sitive antagonist. Matters were aggravated three years later when 

 Newton published his beautiful explanation, on the emission hypothe- 

 sis, of the colors of thin plates. Hooke declared that " the main of it 

 was contained in the ' Micrographia,' " a remark extremely offensive 

 to Newton, who, however, with his usual careful justice, immediately 

 extended his somewhat scanty acknowledgment of his rival's labors, 

 by defining with scrupulous accuracy the measure in which he was in- 

 debted to him. That Hooke was not devoid of generous sentiments 

 appears from a letter which he wrote about this time to Newton, pro- 

 posing a private correspondence on philosophical subjects.* In it he 

 acknowledges the superior abilities of the great mathematician, pro- 

 fesses a dislike to contention, and hints that their relations had been 

 embittered by the machinations of ill-disposed persons. (Oldenburg is 

 evidently indicated.) Newton's reply was conceived in a correspond- 

 ing spirit ; but the harmony thus established was unhappily not last- 

 ing. 



The problem of gravity was the supreme question of that time. It 

 stood first among the orders of the day of the scientific council. It 

 was instinctively felt that, until it should be disposed of, no real prog- 

 ress could be made in physical knowledge. And, slowly but surely, 

 the way was being prepared for a great discovery. Galileo had made 

 Newton possible. Men's ideas were gradually clarifying ; the great 

 cosmical analogies, now so familiar, were step by step emerging out of 

 the dusk of ignorance ; antiquated prepossessions were sinking, in a 

 sediment of cloudy cavil, out of sight. Heaven was assimilated to 

 earth, and earth to heaven ; the old gratuitous separation between the 

 starry firmament over our heads and the solid globe under our feet 

 was abolished by acclamation, and it was felt that the coming law, to 

 be valid, must embrace in its operation the whole of the visible uni- 

 * Brewster, "Life of Newton," vol. i., p. 138. 



