150 PHILOSOPHICAL TRANSACTIONS. [aNNO 1714. 



and declined to contend with any body else, notwithstanding that Mr. Newton 

 in his letter of Oct. 24, 1676, had told him, that for the sake of quiet, he 

 had 5 years before that time laid aside his design of publishing what he had 

 then written on this subject, and has ever since industriously avoided all dis- 

 putes about philosophical and mathematical subjects, and all correspondence by 

 letters about those matters, as tending to disputes ; and for the same reason he 

 has forborn to complain of Mr. Leibnitz, till it was showed him that he stood 

 accused of plagiarism in the Acta Lipsiae, and that what Mr.Keill had published, 

 was only in his defence from the guilt of that crime. 



Is has been said the Royal Society gave judgment against Mr. Leibnitz, 

 without hearing both parties. But this is a mistake. They have not yet given 

 judgment in the matter. Mr. Leibnitz indeed desired the Royal Society to 

 condemn Mr. Keill, without hearing both parties; and by the same sort of 

 justice they might have condemned Mr. Leibnitz without hearing both parties; 

 for they have an equal authority over them both. And when Mr. Leibnitz 

 declined to make good his charge against Mr. Keill, the Royal Society might in 

 justice have censured him for not making it good. But they only appointed a 

 committee to search out and examine such old letters and papers as were still 

 extant about these matters, and report their opinion how the matter stood, 

 according to those letters and papers. They were not appointed to examine 

 Mr. Leibnitz or Mr. Keill, but only to report what they found in the ancient 

 letters and papers : and he that compares their report therewith, will find it 

 just. The committee was numerous and skilful, and composed of gentlemen 

 of several nations, and the society are satisfied in their fidelity in examining 

 the hands and other circumstances, and in printing what they found in the 

 ancient letters and papers so examined, without adding, omitting or altering 

 any thing in favour of either party. And the letters and papers are by order of 

 the Royal Society preserved, that they may be consulted and compared with the 

 commercium epistolicum, whenever it shall be desired by persons of note. And 

 in the mean time I take the liberty to acquaint him, that by taxing the 

 Royal Society with injustice in giving sentence against him, without hearing 

 both parties, he has transgressed one of their statutes, which makes it expul- 

 sion to defame them. 



The philosophy which Mr. Newtony in his Principles and Optics, has pur- 

 sued, is experimental ; and it is not the business of experimental philosophy to 

 * teach the causes of things, any further than they can be proved by experi- 

 ments. We are not to fill this philosophy with opinions which cannot be 

 proved by phaenomena. In this Philosophy Hypotheses have no place, unless 

 as conjectures or questions proposed to be examined by experiments. For this 



