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Viruses are free to mutate into an infinite variety of functionally equivalent forms, whereas the process of establishing their equivalence is undecidable .
And we know that 1st order logic is undecidable ,
Godel showed that in any formal system adequate for number theory there is an undecidable formula, that is, a formula such that neither it nor its negation can be proved.
All we could achieve by our mathematics would be non-constructive existence proofs that told us that they existed, in much the same manner that we can deduce the existence of undecidable propositions.
In Undecidable theories Tarski showed that group theory, lattices, abstract projective geometry, closure algebras and others mathematical systems are undecidable .
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