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Counterexample Method

Can you show me how to use the counterexample method to prove the following categorical syllogism invalid.
"All criminals who assist other criminals in bank robberies are persons guilty of larceny. Accordingly, some individuals driven by greed are not persons guilty of larceny, inasmuch as some criminals who assist other criminals in bank robberies are individuals driven by greed."

I have it set up so that:
C= criminals
P=persons guilty of larceny
D=driven by greed

Solution Preview

The idea behind the counterexample method is to construct a parallel argument (i.e. of the same logical form) which has true premises and a false conclusion.
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<br>Here is the structure of the given argument:
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<br>Premise 1:
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<br>All criminals who assist other criminals in bank ...

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