, C ''*■] 
place it above the State of an Hypothefis, and fiiew 
us we have been right in our Inferences. Mere Ana- 
logy, founded only upon one or two Fads, and 
extended by Conjedure, however plaufible, can but 
at molt furnifh Motives for a reafonable Doubt, and 
a more mature Enquiry. For tho’, as a modern Au- 
thor obferves very well, Nature feems every-where 
to hold with itfelf, and go off by an almoft imper- 
ceptible Gradation j yet, in our prefent Ignorance 
of the entire Chain of Beings, we are fo liable to 
miftake two diftant Species for the next immediate 
ones to each other, that the Analogy is thereby 
nearly extinguifhed, and its Traces almoft effac'd. 
§ 6 . That this has been too much the Cafe in all the 
modern Syftems of Generation, will appear I believe 
plain in the Courfe of this Memoir to every un- 
biafs’d Naturalift. Animalcules were found univer- 
fally in ail animal Seed, almoft at all times, and feem- 
ingly in this animal Secretion alone 5 they were 
therefore previoufly thought efiential to Generation; 
or they fhould have added, a neceflary Confequence 
of Properties in the Seed, which Properties were 
eflential to Generation. But this Inference, how- 
ever natural, was intirely overlook'd by them in 
their Reafoning; and Analogy induc’d them to Bop 
at the firff, without ever examining the fecond, 
tho’ equally confequent. The Opinion of pre- 
exiftent Germs had prevail’d, under the Notion of 
Female Eggs, ere this Difcovery was made; and 
thus one Miftake had been grafted upon another.. 
When the fpermatic Animals appeared, it was not 
difficult to transfer thefe imaginary Germs from the 
one to the other ; and at moil Philofophers were 
only 
