Logic is a language like English, just a lot more precise. That means it's generative. There's no limit to the length and variation of things you can say, and each logical expression semantically entails certain valid conclusions. Short of proof -theoretic axioms like "if A and B, then B," there can't be a finite list.
There is sort of a solution, though. If you limit the number of premises and the number of terms in each premise, you can get a long but finite list. In the Middle Ages, scholastic philosophers trying to build on Aristotle went about listing all the valid categorical syllogisms. They gave them weird names.
@tutordavidlevine115 I have been wanting exactly what you described. I think it will help to better see the task at hand as well. Sometimes I work better backwards, if that makes sense. If I could see the final result I could figure out how to get there. I haven't actually stopped to match up any forms though. Good to see someone else is thinking along the same lines.
Also, as you encounter more arguments in your studies, I'd advise writing out arguments that match up with each argument form. In other words, for each abstract form, you'll write out an actual LSAT stimulus that corresponds with the abstract form. That way you can better hone your powers of recognizing the abstract form in concrete arguments. You can also do this with common flaws.
This exercise, which will take some time, is far more beneficial than someone giving you a summary PDF of the valid and invalid arguments.
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4 comments
Not PDF summary, but I really like the quizzes in core curriculum about valid and invalid argument forms.
Logic is a language like English, just a lot more precise. That means it's generative. There's no limit to the length and variation of things you can say, and each logical expression semantically entails certain valid conclusions. Short of proof -theoretic axioms like "if A and B, then B," there can't be a finite list.
There is sort of a solution, though. If you limit the number of premises and the number of terms in each premise, you can get a long but finite list. In the Middle Ages, scholastic philosophers trying to build on Aristotle went about listing all the valid categorical syllogisms. They gave them weird names.
It's fun to check them out every now and then.
https://en.m.wikipedia.org/wiki/Syllogism
@tutordavidlevine115 I have been wanting exactly what you described. I think it will help to better see the task at hand as well. Sometimes I work better backwards, if that makes sense. If I could see the final result I could figure out how to get there. I haven't actually stopped to match up any forms though. Good to see someone else is thinking along the same lines.
Make your own! :)
Also, as you encounter more arguments in your studies, I'd advise writing out arguments that match up with each argument form. In other words, for each abstract form, you'll write out an actual LSAT stimulus that corresponds with the abstract form. That way you can better hone your powers of recognizing the abstract form in concrete arguments. You can also do this with common flaws.
This exercise, which will take some time, is far more beneficial than someone giving you a summary PDF of the valid and invalid arguments.