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must have taken place before the creation of the present race 
of men, and therefore before the Flood ; and therefore the 
Deluge must have been partial, or else it would have altered 
their appearance. The whole argument falls into a syllogistic 
form thus : — If there has been no eruption since the Flood, 
the mountains would have exhibited traces of the Flood, sup- 
posing it total; but there has been no eruption since the 
Flood ; therefore the mountains would exhibit traces of the 
Flood/ if total. If the Flood were total, the mountains would 
exhibit traces of it ; but they show no such traces ; therefore 
the Flood was not total. This is what logicians call technically 
a double hypothetical, first constructive, then destructive. No 
possible doubt can exist of the truth of either major, considered 
as a hypothesis ; and the minor of the second hypothetical is a 
matter of observation. The correctness of the argument there- 
fore depends on the correctness of the first minor, “no eruption 
has taken place since the time of the Flood/" This proposition 
is proved as follows. No event of which there is no record ever 
took place ; a post-diluvial eruption of these mountains is an 
event of which there is no record ; therefore none such ever 
took place. This syllogism is correct in form ; but the major 
is palpably false, and I rather think the minor is not altogether 
certain. I believe that allusions have been found to a volcanic 
eruption in or near the district in question ; and we know from 
the example of Vesuvius previous to the eruption of 79 A.D. 
that a long period of inactivity is not impossible in a volcanic 
district. The fallacy of negation is contained, however, in the 
major. Is it true that no unrecorded event ever took place ? 
Are we to suppose that the rude Kelts, or the still earlier Fins, 
or Euskara, of the country we now call France, preserved any 
records or traditions of natural phenomena ? Are we to suppose 
that the Roman invaders, in 125 B.C., would have cared to 
collect and retain such records and traditions, had they been 
preserved up to the invasion ? or that the Greek colonists of 
Massilia in 600 B.C. would have carefully handed down to their 
children the vague traditions of a number of savages ? Nay, 
more, have we in our possession all the papers and documents 
treating of the physical aspect of Gallia Braccata, so as to be 
certain that none of them mention a tradition of the Arverni,that 
Divine fire had once been kindled on the summit of their hills ? 
Men must be prepared to assert the probability, at least, of 
all this, if they employ this argument in the manner I have de- 
scribed. If they are not prepared to make such an assertion, 
their argument is fallacious. 
While I am on the subject of errors connected with induc- 
tive reasoning, I must not omit another fallacy, which can be 
