Garrath Williams, in his "Kant's Account of Reason", discusses the unity of theoretical and practical reason. He notes that in a footnote to one (relatively short) essay, Kant says:
To make use of one’s own reason means no more than to ask oneself, whenever one is supposed to assume something, whether one could find it feasible to make the ground or the rule on which one assumes it into a universal principle for the use of reason.
Williams observes that this sounds like a categorical imperative. "To rephrase the point: Thinking and judging are activities. If the Categorical Imperative is truly 'categorical' then it applies to all our activities—'theoretical' as well as 'practical.'" And so he goes on to quote Kant regarding another set of such principles:
The precept for reaching [wisdom] contains three leading maxims: (1) Think for oneself, (2) Think into the place of the other [person] (in communication with human beings), (3) Always think consistently with oneself.
Lastly, there is the "public use of reason":
Kant equates reason with full publicity. “To use one’s own reason” is to make a sincere attempt to address all “citizens of the world.” Judgments and principles are only reasonable to the extent that they can be accepted by all. Our actions must respect existing boundaries and governments, because the duty to pursue and maintain peace is categorical. But reason itself aspires to universality. So as citizens of the world, we have another categorical duty: to see ourselves as accountable to every human being, and hence to improve existing institutions so that they recognize the claims of all.
It is Onora O'Neill who Williams mentions in broad connection with these points. For more on the Kantian link between normativity for theoretical assertions and normativity for practical ones, see her "Kant on Reason and Religion".
The SEP also covers a discussion of metaepistemological realism in which one theorist, Terence Cuneo, is cited as proposing an argument jointly grounding a belief in normative facts about moral beliefs and epistemic ones:
- If moral facts do not exist, then epistemic facts do not exist.
- Epistemic facts exist.
- So, moral facts exist.
- If moral facts exist, then moral realism is true.
- So, moral realism is true.
John Turi, et. al.'s "Virtue Epistemology" goes over an aretaic ethics of belief/knowledge. They give an overview of how this general thesis (more a question, really, rather) can be cashed out more locally:
[Some] think that epistemology should aim to promote intellectual well being. Perhaps an epistemological theory should be “practically useful” in helping us recognize when we do or don’t know something (Zagzebski 1996: 267), or help us overcome “anxieties” due to defective presuppositions about knowledge (McDowell 1994: xi; Pritchard 2016a). Perhaps epistemology should help us appreciate and respond to forms of “epistemic injustice” (Fricker 2007). Perhaps epistemology should inspire us with portraits of intellectual virtues, thereby promoting cultural reformation and intellectual flourishing (Roberts & Wood 2007). Perhaps epistemology should examine intellectual vices and other defects to tell cautionary tales of what not to do and how not to be (Alfano 2015, Battaly 2014, Cassam 2016). Or perhaps practitioners should help redesign educational institutions to help students cultivate intellectual virtues (e.g., the Intellectual Virtues Academy—see Other Internet Resources).
Beyond that, they note the typical division of the thesis into two main camps:
[Virtue epistemology] is standardly divided up into virtue responsibilists and virtue reliabilists (e.g., Axtell 1997). According to this taxonomy, the two camps differ over how to characterize intellectual virtue. Virtue reliabilists (e.g., Goldman, Greco, and Sosa) understand intellectual virtues to include faculties such as perception, intuition, and memory; call these ‘faculty-virtues’. Their view is best understood as a descendant from earlier externalist epistemologies such as simple process reliabilism. Virtue responsibilists (e.g., Battaly, Code, Hookway, Montmarquet, and Zagzebski) understand intellectual virtues to include cultivated character traits such as conscientiousness and open-mindedness; call these ‘trait-virtues’. Their approach is broadly aligned with internalist sympathies in epistemology and deeply concerned with cognition’s ethical dimensions and implications.
Note that even if normativity for beliefs is given, this might be a normativity of permissions more than obligations. Science might be permitted, but a genuine skepticism might be accommodated (i.e. a sincere skepticism, not the selectively convenient paranoia of political agitators on the Internet right now), and perhaps a "disjunctive theology" or religiosity. (We would maintain that it is permissible to believe in disjunctions over different religious propositions, e.g., "Either there is One True God, or there are infinitely many deities, or the world itself is conscious/divine (and there could be an infinite pantheon of world-soul deities in a multiverse), or there are no divine beings, or..." and however large the disjunction ends up being, we are not permitted to eliminate any of its disjuncts by reasoning, but must sustain the disjunction "as is" if we apply our permission to believe in it at all.)