Hi dallas and welcome,
You'll see that the logging categories, to over-simplify, range in importance from critical down to mildly interesting -- actually I think "all events" is at the bottom of the list.
Whichever category you pick as your cutoff point, that plus all more-important categories (i.e., those higher on the list) will be logged. So if you pick the top one, only that one will be logged, while picking the bottom one will log all categories.
What you describe is half-correct, in the sense that you can only view one category at a time, but other categories may also be active depending on your settings.
Best,
Mike