Among the diversity of logical issues, the most profound and fundamental issues in logic concern the choice of the inferential logic itself. I will discuss the following four issues that need to be addressed in association with the choice of logic. (I) Classical versus non-classical logic. (II) The determination of a particular non-classical logic (given discussion of (I)). (III) Classical versus non-classical deduction. (IV) Classical versus non-classical meta-logic. I will also address the following two sub-issues whilst discussing (I). (i) What is deductive logic all about? (ii) Is there a guaranteed domain of classicality?