«Assertion and Isolated Secondhand Knowledge Jennifer Lackey Northwestern University A common view in the recent philosophical literature is that ...»
Forthcoming in Jessica Brown and Herman Cappelen (eds.), Assertion (Oxford: Oxford University Press).
Assertion and Isolated Secondhand Knowledge
A common view in the recent philosophical literature is that knowledge is the norm governing
proper assertion. Thus, according to Keith DeRose, “…one is positioned well-enough to assert that
P iff one knows that P” (DeRose 2002, p. 180). Let us call the thesis expressed here the Knowledge
Norm of Assertion, or the KNA, and formulate it as follows:
KNA: One is properly positioned to assert that p if and only if one knows that p.
As stated, there are two dimensions to the KNA; one is a necessity claim and the other is a
sufficiency claim. More precisely:
KNA-N: One is properly positioned to assert that p only if one knows that p.
KNA-S: One is properly positioned to assert that p if one knows that p.
Much attention has been devoted to the KNA-N, both in terms of arguments presented on its behalf and in terms of objections offered to challenge it. 1 I shall not here contribute to this debate.
Instead, I shall restrict my focus to the KNA-S which, by comparison, has been the explicit topic of relatively few extended discussions. 2 Now, while clear endorsements of the KNA-S tend to be more implicit or undeveloped than those of the KNA-N, they are nonetheless quite prevalent. For instance, immediately prior to arguing that knowledge is the norm of assertion, Steven Reynolds poses the question, “what epistemic relation to p is good enough to make it permissible to assert that p?” (2002, p. 140).
Similarly, shortly after defending the KNA-N, John Hawthorne adds that it may also be “arguable that knowledge suffices” for the “epistemic correctness” of assertion (2004, p. 23, fn. 58). And, according to John Hawthorne and Jason Stanley, “Where one’s choice is p-dependent, it is appropriate to treat the proposition that p as a reason for acting iff you know that p” (2008, p. 578).
Thus, if assertion is a species of action, knowing that p is both necessary and sufficient for properly asserting that p. In all of these passages, then, we find different characterizations of the KNA-S. 3 Surely, however, even if I unquestionably know that my colleague made a fool of himself while we were all drinking the other night, it may still be improper for me to assert that this is the case on Monday morning. It may, for instance, be imprudent because it would strain our friendship;
or it may be impolite because he would find it utterly embarrassing; or it may simply be pointless because everybody in the department already knows that this is the case. So in what sense is knowing that p sufficient for one to be properly positioned to assert that p?
The answer to this question can be found in the quoted passages above. Reynolds, for instance, asks what epistemic relation to p is good enough for the permissibility of assertion, and Hawthorne talks about knowledge being sufficient for the epistemic correctness of assertion. Given this,
let us clarify the sufficiency claim as follows:
According to the KNA-S*, then, knowledge is sufficient for possessing the epistemic authority for assertion even if it is insufficient for various other kinds of propriety. For instance, while it may be imprudent, impolite, or pointless for me to assert that my colleague behaved foolishly over the weekend, my knowing that this is the case suffices for my having the epistemic credentials to make such an assertion.
The KNA-S* has a great deal of intuitive appeal. If I assert that the university is closed because of an impending snowstorm, my knowing that this is the case seems sufficient to render such an assertion permissible. If my assertion is questioned, appealing to my knowledge adequately meets the challenge, while offering anything less—such as my suspecting that the university is closed, or being moderately justified in believing that it is—does not. Moreover, the KNA-S* has
significant theoretical power. According to DeRose:
The knowledge account of assertion provides a powerful argument for contextualism: If the standards for when one is in a position to assert warrantedly that P are the same as those that constitute a truth condition for “I know that P,” then if the former vary with context, so do the latter. In short: The knowledge account of assertion together with the context sensitivity of assertability yields contextualism about knowledge. (2002, p. 147) This link between knowledge as the norm of assertion and contextualism requires both the necessity claim and the sufficiency claim of the KNA, and so the truth of the KNA-S* provides critical support to a central argument on behalf of contextualism.
Despite the intuitive plausibility and theoretical power of the view that knowledge suffices for epistemically permissible assertion, however, I shall argue in what follows that the KNA-S* is false. In particular, I shall show that there are various kinds of cases in which a speaker asserts that p, clearly knows that p, and yet does not have the proper epistemic authority or credentials to make such an assertion, thereby showing that knowledge is not always sufficient for epistemically proper assertion. I shall then offer a diagnosis of what is salient in the cases challenging the KNA-S*, and suggest a broad feature that needs to be accounted for in any view of the norm governing proper assertion.
1. Isolated Secondhand Knowledge—Expert Testimony To begin, consider the following three cases, all of which involve a phenomenon that I shall call
isolated secondhand knowledge:
DOCTOR: Matilda is an oncologist at a teaching hospital who has been diagnosing and treating various kinds of cancers for the past fifteen years. One of her patients, Derek, was recently referred to her office because he has been experiencing intense abdominal pain for a couple of weeks. After requesting an ultrasound and MRI, the results of the tests arrived on Matilda’s day off; consequently, all of the relevant data were reviewed by Nancy, a competent medical student in oncology training at her hospital. Being able to confer for only a very brief period of time prior to Derek’s appointment today, Nancy communicated to Matilda simply that her diagnosis is pancreatic cancer, without offering any of the details of the test results or the reasons underlying her conclusion. Shortly thereafter, Matilda had her appointment with Derek, where she truly asserts to him purely on the basis of Nancy’s reliable testimony, “I am very sorry to tell you this, but you have pancreatic cancer.” EXPERT PANELIST: In the wake of the Space Shuttle Challenger disintegration, the United States House Committee on Science and Technology conducted a hearing in an effort to determine the cause of the disaster. One of the experts called to testify at the hearing was John Smith, a manager at NASA. Though it was part of Smith’s responsibilities to monitor the details of the shuttle operation, both before and after the accident, he has been preoccupied with personal problems and has thus been negligent in carrying out his official duties. On the morning of the hearing, Smith met very briefly with one of his co-workers who told him only that the cause of the shuttle’s disintegration was the failure of an O-ring seal at liftoff. Despite the fact that Smith is not privy to any of the data or reasoning underlying this explanation, and has only his co-worker’s reliable testimony to ground his belief, he truly asserts at the House Committee hearing, “The Space Shuttle Challenger disintegrated because of the failure of an O-ring seal at liftoff.” 4 PROFESSOR: Judith is a professor at one of the best law schools in the country, and today’s lecture is on U.S. copyright law. While she is generally quite knowledgeable of this topic, she has failed to keep up with some recent developments in this area. Over lunch yesterday, one of her colleagues briefly expressed his belief that it is extremely improbable that the Supreme Court will consider a case challenging the addition of 20 years to the original copyright protection of 50 years after the death of authors. Though Judith does not know any of the reasons or considerations underlying this claim, she asserts to her students in class, “The Supreme Court is unlikely to hear the upcoming challenge to the recent extension of U.S. copyright protections to 70 years after the author’s death.” While this assertion is in fact true, it is based purely on the basis of the reliable testimony of Judith’s
Though there are some interesting differences among these cases, they are united in all involving what I earlier called isolated secondhand knowledge. There are two central components to this phenomenon: first, the subject in question knows that p solely on the basis of another speaker’s testimony that p—hence the knowledge is secondhand; and, second, the subject knows nothing (or very little) relevant about the matter other than that p—hence the knowledge is isolated. The combination of these features, by itself, is not necessarily problematic, even when assertion is involved. But when a subject’s assertion that p is grounded in such knowledge in contexts where the hearer reasonably has the right to expect the asserter to possess more than merely isolated secondhand knowledge, there is a problem.
To see this, let us begin by considering DOCTOR. The first point to notice is that Matilda clearly knows that Derek has pancreatic cancer—it is true, she believes it, she has good reason to trust the testimony of her medical student, and Nancy is in fact a reliable source. Given that Matilda herself has not reviewed any of the results of Derek’s test, and has no independent information supporting the diagnosis of pancreatic cancer in this case, it is equally clear that Matilda’s knowledge is both secondhand and isolated. Of course, qua oncologist, Matilda knows a great deal about pancreatic cancer in general, and she has some limited data about Derek’s symptoms from meeting with him. But this broad information in no way grounds the specific knowledge in question— abdominal pain is, after all, a sign of numerous conditions, ranging from gallstones and food poisoning to intestinal obstructions and appendicitis. The knowledge that Matilda possesses that Derek in particular has pancreatic cancer, then, is grounded entirely in Nancy’s testimony, and she has no additional information relevant to this specific diagnosis other than the fact that her student communicated to her. The question we must now consider is whether, under these conditions, Matilda is properly epistemically positioned to flat out assert to Derek that he has pancreatic cancer.
And here the answer is clearly no. For while Nancy’s reliable testimony may be sufficient for Matilda’s knowing that Derek has pancreatic cancer, and while its isolated nature may not pose an epistemic obstacle to this being the case, the isolated secondhand nature of Matilda’s knowledge makes it improper for her to flat out assert this diagnosis to Derek. One reason for this is that Matilda is an expert—she is an oncologist and Derek’s physician, and such roles carry with them certain epistemic duties. In DOCTOR, these responsibilities may include having reviewed the test results firsthand, possessing reasons for choosing one condition over another, knowing details about the size and nature of the cancer, and so on. But the overarching epistemic duty here is that, qua oncologist, Matilda should be able to (at lest partially) explain or justify the diagnosis of pancreatic cancer that she is offering to her patient. Moreover, as her patient, Derek reasonably has the right to expect his doctor to fulfill such a duty. Suppose, for instance, that he asks Matilda what exactly the ultrasound and MRI revealed, or how large his tumor is, or why she thinks it is pancreatic cancer, and she is unable to answer any of these questions. Indeed, suppose that she reveals to Derek that she had been told that he has pancreatic cancer from her student Nancy, that she hadn’t actually seen any of the test results herself, and that she has no additional information to offer about his particular diagnosis. Wouldn’t Derek be entitled to resent Matilda under such circumstances, to feel that he has been epistemically cheated by his doctor who owes him more than a diagnosis grounded purely in isolated secondhand knowledge? The upshot of these considerations, then, is that in DOCTOR, we have a case where a speaker knows that p without thereby being epistemically positioned to properly assert that p, thereby falsifying the KNA-S*.