282 ON SPONTANEOUS GENERATION. 



appeared, which cannot be accounted for otherwise. Is as- 

 sertion to take the place of positive facts, and is not this 

 mere assertion ? How can we prove that there were no germs 

 of that type of organisms in that place where we now ob- 

 serve the organism in question ? We find, when we begin to 

 examine it, that it produces germs itself; then, by what parity 

 of reasoning can we assert, that it has sprung from matter 

 without any previous germ, when we find, in every succeeding 

 instance, a germ is always given for a succeeding organism ? 



Philosophers are too much in the habit of considering 

 themselves bound to assign a cause for every extraordinary 

 proceeding in nature, as soon as observed, instead of candidly 

 confessing their ignorance upon the subject, as though it 

 would disgrace them to own that there were some subjects 

 on which they possessed no more knowledge than the most 

 unlearned. What ridiculous theories we should have been 

 spared the pain of observing attached to respectable names, 

 had they acted as above ; but instead of proceeding upon 

 experiments and facts, and adapting their superstructure to 

 the knowledge so obtained, they boldly assume a position, 

 propound a theory in accordance with it, and then strive to 

 support it by placing the most favourable observations in 

 direct support, and wresting the unfavourable ones from their 

 legitimate bearings and deduction to support it. This has 

 happened with the advocates of many doctrines, and in 

 nearly every branch of natural science. 



I can as easily believe that spontaneous generation can 

 produce the largest, or the most complex organism, as that 

 it can produce the smallest, or the most simple. Why should 

 the operation of it be confined in general to the lower grades 

 of organisms, both animal and vegetable, by the advocates 

 of it, but solely because they know that they are unable to 

 bring the slightest reason (much less fact) in support of 

 their doctrine ? If they apply it to the larger, the universal 

 experience of all mankind is against them. It is an idea com- 

 monly held by many of the most ignorant and illiterate per 

 sons, that Pediculi are generated spontaneously owing "to an 

 ill habit of body ; and I have known instances where the 

 appearance of a single specimen of Ped. vesiiamenti (P. 

 corporis humani, Weiss.), would throw a whole family into the 

 greatest inquietude, being regarded as the precursor of se- 

 vere bodily illness, or trouble in worldly affairs. With regard 

 to the statement of cleanliness preventing the operation of 

 spontaneous generation in producing the various species of 

 Pediculi, I can easily understand how cleanliness may re- 

 move them after generation ; but I must confess my obtuse- 



