Introducing deductive validity

Here we introduce the key concept of deductive validity. Here’s our official definition of the concept:

• An argument is deductively valid if, and only if, it is not possible for it to be the case that both (i) all of its premises are true and (ii) its conclusion is false

(Because this is an important step, we’ve included a formatted text version in case you’d like to review and refer back to that once you’ve watched the video. Please see the link below.)