CSCE 222 Lecture 8

Class canceled on Feb 4 due to inclement weather

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Arguments

a sequence of propositions (premises) that result in a conclusion

Modus Ponens

If you have a current password, then you can log on to the network"

You have a current password, therefore you can log into the network

${\begin{array}{l}p\\p\rightarrow q\\\hline \therefore q\end{array}}$

Modus Tollens

"The university will not close on Wednesday"

"The university will close if it snows, therefore it will not snow on Wednesday"

${\begin{array}{l}\neg q\\p\rightarrow q\\\hline \therefore \neg p\end{array}}$

Simplification

${\begin{array}{l}p\wedge q\\\hline \therefore p\end{array}}$