AMERICAN EDITION. xvii 



^thefe introduftory remarks may perhaps afford fome gratification. 

 Others, who porTefs not the tafte or leifure for fuch enquiries, raay pafs 

 them over, and in the progrefs of obfervation and experiment in phyfics, 

 within a few years, fuch a number of new and important facts have 

 been brought to light, that many philofophers have believed the peo- 

 ple of the prefent day were pofTeffed of a great deal more knowledge 

 than the moderns of the three laft centuries, or their ancieot prede- 

 ce/Tors. 



This opinion, in particular, has been deemed well founded, and true 

 in its refpect to medicine, which, at this time, is not only confidered 

 fufceptible of new expofitions and interpretations, but of being great- 

 ly improved and enlarged, both in theory and practice. And although 

 among thofe who think thus are reckoned moft of the original and clear 

 fighted geniufes of our time, yet there are not wanting fome, and thofe 

 iften of talents and reputation too, who are in the habit of thinking, if 

 the ancients knew not quite as much as ourfelves, yet their writings 

 contain the leading hints, or great outlines of almoft every thing dif- 

 coverable, either directly exprefled, or fignified in allegorical terms. 

 This literary fuperftition has been carried a great way ; and if it had 

 flopped at declaring the Iliad the belt of poffible poems, or the Pkil- 

 lipics the moft finifhed of the rhetorical productions, I mould not at 

 this time have troubled myfelf to contradict it. But when thefe 

 enthufiaftic admirers of antiquity declare, that, in matters of fcience as 

 well as of letters, the fubjects of enquiry have been exhaufted two 

 thoufand years ago, and that no idea can be (rarted which is not an 

 imitation of fomething that a Greek or a Roman, or fome body elfe, 

 had thought before, I own I am a little difpofed to believe their 

 aflertions are grounded neither in truth nor in the nature of things. 

 For why muft we refort to the PLATONISTS, STOICS, and PERIPA- 

 TETICS, for doctrines which the ACADEMY, the PORCH, and the LY- 

 CEUM never knew ? 



Thefe remarks are made in confequence of an opinion, propagated 

 and believed by fome, that a certain method of reafoning upon medical 

 fubjects, and of medical practice introduced now of late as many be- 

 lieve, which are already pretty well eftabli^hed, and acquiring rapidly 

 more and more adherents, are in fact but a revival and new modelling 

 of the opinions and procedure of the METHODIC SECT, founded by 

 ASCLIPIADES, the extemporary of MITHR.IDATIJS and CRASSUS 



In order to know whether this opinion is well founded, I mail en- 

 quire what the philofophy of the Methodic .Sect was. 



Its founder, ASCLEPIADES } adopted that philofophy, whofe foun- 

 dation had been laid by ANAXAGORAS, JtMPtDocLEs, and HERACLI- 

 TUS, and which was afterwards wrought up into the Atomic Sy/iem* by 

 LEUCIPPUS, and DEMOCRITUS, ofthzE/wtic Sift ; who, rejecting all 

 metaphyfical explanations of the caufes of things, undertook the inter- 

 preting nature, from the laws of matter and motion. This was after- 

 wards commented upon, enlarged and adorned by EPICURUS, fo as 

 foform, what was afterwards called the Epicurean Philofopby. What 

 :lie details of this are, may be feen in DIOGENES LAERTIUS, in 



VOL. L ERUCKER 



