[«DG»Typhoon]

You absolutely could - the terms are relative and your use of them stems from whatever moral code you've developed as time progresses.

If something isn't good, is it automatically bad?

You could have a "bad" day, but is that a "bad" day as opposed a "good" day, or some other kind of day?

However, if nothing is good, can anything be "bad"?

*insert something from nothing vs nothing from nothing debate here*