Suppose there are epistemic norms of assertion, belief, and practical reasoning. According to Williamson (2000), knowledge is the norm of assertion:
KA: You ought not assert p unless you know p but are warranted in asserting p if you know p.
According to Hawthorne and Stanley (2008), knowledge is the norm of practical reasoning:
KPR: You ought not treat p as a reason for acting (for some p-dependent choice) unless you know p but are warranted in treating p as a reason for action if you know p.
According to Sutton (2007), knowledge is the norm of belief:
KB: You ought not believe p unless you know p but are permitted to believe p if you know p.
There is a simple and powerful argument against each of these proposals. These norms are epistemic norms. KA says that if you don’t know p, there is a conclusive epistemic reason to refrain from asserting p or an undefeated epistemic reason not to assert p. KPR and KB tell us there are similar reasons that bear on whether to believe and whether to treat something as a reason for action when deliberating about what to do. These norms tell us nothing about the non-epistemic case for or against asserting, believing, or treating something as a reason for action. Think about KA and KPR. Does the epistemic assessment of assertion or treating something as a reason for action tell us something about the normative standing of the agent’s beliefs? Will situations arise where we say that you believed what you should have concerning p but weren’t in a position to assert that p is true? Will situations arise where we say that you believed what you should have concerning p but weren’t in a position to treat p as a reason for Φ-ing when we acknowledge that you knew that Φ-ing was the thing to do if p? It doesn’t seem that the conditions under which it’s appropriate to believe p and to express your belief by saying that p is so differ in any significant way, whatever epistemic case is to be made against the act of speaking your mind should constitute an epistemic case against forming the belief you did. It doesn’t seem that the conditions under which it’s appropriate to believe are but a proper subset of the conditions under which it’s appropriate to rely on that belief when you know the content of the belief is what matters to the relevant bit of reasoning. So, it is tempting to say that the following links hold:
BPR: If you conform to the epistemic norms that govern belief by believing p, you conform to the epistemic norms governing practical reason by treating p as a reason for action (for some p-dependent choice).
BA: If you conform to the epistemic norms that govern belief by believing p, you conform to the epistemic norms governing assertion by asserting that p is the case.
These knowledge norms tell us whether it is epistemically permissible to believe, assert, or treat something as a reason for action. According to BPR and BA, there aren’t different epistemic standards that apply to beliefs on the one hand and the expressions of belief or reliance on belief in reasoning on the other. Because we don’t rely on some two-stage process of epistemic assessment to determine whether someone who believes has the warrant to speak her mind or reason from what she takes herself to know, I think it’s clear that we assess things epistemically as if we accept BPR and BA. To be justified in believing p requires that you believe p permissibly. It can’t be that you shouldn’t believe p, but you believe p justifiably. Two things of consequence follow. First, a commitment to either KA or KPR comes with a commitment to KB. Second, a commitment to KB comes with a commitment to KJ:
KJ: You can’t justifiably believe p unless you know p.
The problem, of course, is that KJ is false. Gettier cases show that it’s possible for someone to justifiably believe something they don’t know to be true. So, we can see that knowledge isn’t the norm of assertion, practical reasoning, or belief. The problem isn’t just that there are counterexamples to KJ. The real problem is that if we acknowledge that knowledge and justified belief are distinct because we appreciate that there’s more to knowledge than just justified belief, we should see that it is incoherent to say that the additional factors that distinguish mere justified belief from knowledge should figure in epistemic norms. It is incoherent to say this because to say this, BPR and BA imply that someone can be epistemically prohibited from believing what she permissibly believes. So, if knowledge and justified belief are distinct, there’s no question that it’s justification that’s the norm of assertion and practical reasoning because it’s utterly vacuous to say that justification is the norm of belief.
Note that for all I’ve said, it might be that justified belief is a lot more like knowledge than most epistemologists currently believe. I’ve said that JB is utterly trivial:
JB: You ought not believe p unless you justifiably believe p but are permitted to
believe p if you justifiably believe p.
Combine JB with BA and BPR and we have to say that justified beliefs are whatever those things are that warrant assertion and warrant treating something as a reason for action. If you shouldn’t assert false propositions and shouldn’t treat false propositions as reasons for action, it may well be that the only real difference between justified belief and knowledge are the conditions that make for Gettier cases. There’s little that we can say about all the Gettier cases that is informative and true, but this much seems right. The cases that figure in such conditions almost always seem to involve conditions that have little significance for what we should do or what we should say in those kinds of situations, so perhaps these cases bring to light a variety of normatively insignificant aspects of knowledge.
Hawthorne, J. and J. Stanley. 2008. Knowledge and Action. Journal of Philosophy 105: 571-90.
Sutton, J. 2007. Without Justification. Cambridge, MA: MIT University Press.
Williamson, T. 2000. Knowledge and its Limits. New York: Oxford University Press.