[FOM] Use of Ex Falso Quodlibet (EFQ)

[Tennant, Neil]

Paul Levy writes:

    Or-elimination may be seen as the special case n=2 of n-ary
    or-elimination.  The case n=0 is EFQ.  I can think of no philosophical
    or ideological reason for accepting n=2 but rejecting n=0.

I must respectfully disagree. This is in error. If one were to frame n-ary or-elimination in Core Logic, it would be done graphically thus:

                          __(i)  ...  __(i)
                          A1          An
                           :             :
   A1v...An           B/#        B/#
   _________________________(i)
                         B/#

where this is to be understood as follows:
1. if # is the conclusion of every case-proof (all n of them!), then the main conclusion is # ;
2. otherwise, the main conclusion is B .

There is no case of n-ary or-elimination corresponding to n=0. What on earth would it look like?

Neil Tennant

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