- #1

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- TL;DR Summary
- use of negation in disjunctive amplification

Book shows a proof where a conclusion is reached of: ##\neg r##. The next step says ##\neg r \lor \neg s## using the rule of disjunctive amplification. The rule of disjunctive amplification as I know it is ##p \implies p \lor q##. I don't see how from this you can also say ##\neg p \implies \neg p \lor \neg q##. I can see that the truth table is a tautology so I know it's true, I just don't see how to get there.