Validity and necessary truths
Validity is defined in a couple of ways. I like to define it like this: An argument is valid iff the superconjunction1 of all the premises and the negation of…
Sound arguments and rationally convincing arguments
I've read many times and places that an argument is sound iff 1. The argument is valid. 2. All the premises of the argument are true. [1] Let's call this…
The term non-sequitur
As Wikipedia notes,i the term is used in everyday speech to deny a conditional (if-then statement), and it is also used in logic to mean an invalid argument. This together…