Opposing this, we have Judgmentalism, the view that we're never required to suspend judgment: there's always some doxastic commitment or other that we could at least as reasonably hold.
We might go further and consider Strong Judgmentalism, the view that there is always some doxastic commitment (e.g. some level of credence) that's rationally superior to suspending judgment entirely.
Which of these views is most plausible? And (for any epistemologists in the audience) is there any existing literature on the topic? (I just made up these names, so they might go by different labels if so...)
I find myself drawn to Strong Judgmentalism, but would settle for defending Judgmentalism against Non-commitalism. I see three main routes to doing so:
(1) Co-opt existing arguments against imprecise credence. Since non-commitalism is effectively the view that some particular (namely, maximally open) imprecise credence is sometimes required, existing arguments (e.g. this one) against the rationality of imprecise credence are a fortiori arguments against non-commitalism.
But these are controversial, and have stronger implications than I need. Even friends of imprecise credence can be Judgmentalists, so long as they don't insist that we're ever required to have maximally open imprecise credences. (Maybe we should sometimes have imprecise credences that range over some smaller interval, e.g. 0.4 - 0.6ish.)
(2) Make the intuitive case for Judgmentalism. I'm fond of the slogan, "Use your best judgment, don't suspend it!" Of course it's tendentious: the non-commitalist will say that they use their best judgment in determining whether they possess sufficient evidence to undertake a doxastic commitment -- a judgment (about their evidential state) which might lead them to suspend judgment (about the proposition in question).
But I think there's something to the slogan nonetheless, As I previously put it:
[T]here's nothing especially admirable about answering every philosophical question with "Who knows?" The philosophically mature skeptic would add, "But here are a couple of possible options...", which is certainly a huge improvement. Best of all, it seems to me, would be to further make a tentative judgment as to which of those options is best, and go from there. You can always change your mind later.
I guess suspending judgment is a way to 'play it safe', if it's more important to you to avoid being wrong than to actually get things right. But that seems a kind of intellectual cowardice. Better to actively seek the truth, and if you end up in the wrong place, just turn around and try again.
Here it's important to stress that judgmentalism need not (and presumably should not!) involve a dogmatic attitude. We're not infallible, and when we have very little evidence to go on, we should presumably be especially open to the possibility of subsequently revising our opinions. But that's no reason (it seems to me) not to give it our "best shot" in the meantime.
(3) Flag the theoretical benefits of Judgmentalism. Judgmentalism supports the practice of philosophy against skeptical objections. If we're required to suspend judgment about anything, the irresolvable disputes of philosophy are likely among them. (So non-commitalism itself is probably something that you're rationally required to suspend belief about, if non-commitalism is true.)
Judgmentalism, by contrast, offers a powerful response to the skeptic: "If you think my current level of credence is unjustified, what alternative credence would be better?" If suspending judgment is off the table, then lazy skeptics can no longer rest on their laurels with negative judgments. In order to productively disagree, they must put forward some alternative positive proposal about which credences are most rational.
You might wonder: Even if I'm right that Judgmentalism better supports the practice of philosophy, is this any reason to think Judgmentalism likely to be true, or is it just an invitation to engage in wishful thinking? I'm hoping the former! Seriously though, I think there's a decent case to be made for having some default trust in propositions that are preconditions for knowledge or inquiry. And while there are limits to how far you can push such a principle (even if tarot cards were the only possibility of gaining knowledge of the universe outside our light cone, it wouldn't follow that we should trust in tarot cards as an epistemic method!), I can't think of any particularly strong reasons to reject Judgmentalism.