I. What to Do when Stuck: “Desperate Measures” Following the guidelines suggested above will get you through just about any problem. But there is a certain kind of problem where you still might get stuck in the middle, and you’ll have to try something desperate to get out of being stuck. Here is an example of that kind of problem. 1. 2. 3. ( P ! R ) _ ( Q ! S ) P Q SHOW: R _ S Pr Pr If you follow the guidelines, you’ll begin by starting an ID. A few steps can be done after that. 1. 2. 3. 4. 5. 6. 7. 8. 9. ( P ! R ) _ ( Q ! S ) P Q SHOW: R _ S ⇠ ( R _ S ) SHOW: 6 P Q ⇠ R ⇠ S Pr Pr ID Ass DD 4 ⇠_ O 4 ⇠_ O But, uh oh, now what? There doesn’t seem to be anywhere to go from here. When you get stuck like this, you need to ask yourself: what would be helpful? what resources do you have that you would like to make use of, but can’t? Usually this will lead you to one or more lines that are just begging to be used. In this case, it’s line 1, which hasn’t been
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