valid arguments

esteerose

I am looking to find a place on 7sage (preferably a pdf document) that has all of the 9 valid argument forms written out. Is there a pdf of these? Thanks!

dcdcdcdcdc

You can print these two pages:

1-3: https://7sage.com/lesson/valid-argument-forms-1-3-of-9/
4-9: https://7sage.com/lesson/valid-argument-forms-4-9-of-9/

esteerose

Thank you!! I forgot to star them.. Thanks for the help.

quinnxzhang

Argument form 6 is INVALID. If there are no turtles and if nothing is named after Italian artists, then both premises are true and the conclusion false.

In order for number 6 to be valid, you would need an additional premise: there are some turtles. Maybe this is an innocuous assumption for LSAT purposes, but in the interest of correctness, I think 7sage should at least footnote this. I firmly believe that the logic taught in LSAT courses shouldn't directly contradict the classical logic textbooks informing the logic used on the actual exam.

apublicdisplay

Agreed with @quinnxzhang I've always learned that to take A –> B and A –> C and draw the conclusion B some C, you must assume that there is at least 1 member in A. However, I can't say entirely why the assumption of at least 1 is used for this example and not for other conditional statements.