^A particular sort of argument for the claim that a person’s practical interests can impact whether he or she counts as having knowledge has been advanced by philosophers Jeremy Fantl and Matthew McGrath.
Other notable philosophers who have argued for related conclusions include John Hawthorne and Jason Stanley.
^Fantl and McGrath’s argument goes under the heading of pragmatic encroachment, because it involves the conclusion that pragmatic, or practical concerns, influence or encroach upon questions of whether or not someone has knowledge.
^The structure of Fantl and McGrath’s argument is very simple. Essentially, it rests on two planks: fallibilism and a practical condition on knowledge.
] Fallibilism is the claim that it is possible for someone to know something without having certain knowledge. Given the fact that we’ve adopted fallibilism as a working assumption for the bulk of these lectures—ever since we rejected Descartes’s extreme version of internalism—we’ll continue with the assumption that fallibilism is correct.
] According to the practical condition on knowledge, if you know some fact, then you are rational to act as if that fact is true.
^When you combine fallibilism and the practical condition, you are forced to accept that whether or not someone has knowledge depends in part on his or her practical interests.
Theories of Knowledge LECTURE 22 Pragmatic and Moral encroachment
^It’s very plausible to think that whether it is rational to act as if some fact is true does vary according to your practical interests. The more significant the outcomes of a particular act are for you, the greater evidence you need in order to have reason to act.
^But then, if that’s true, that would imply—because of the practical condition—that the evidence required for knowledge would also vary according to your practical interests.
^That, however, just is the claim endorsed under the heading of pragmatic encroachment. That is because what this conclusion means is that whether or not you have knowledge can depend on the level of importance a fact has for you.
The more important the fact is for you, the more evidence you would need in order to know that fact. For trivial facts, though, you could have knowledge with far less evidence.
^Why should we accept the claim that whether it is rational for you to act as if a certain fact is true depends on your practical interests?
^Suppose you believe that whenever you eat peanuts you get headaches—
not debilitating headaches, but annoying ones. If that’s the case, then you might want to look out on menus for a disclaimer stating that
the restaurant does not use peanuts or peanut products in preparing its food.
Once you see that disclaimer, you’ll feel comfortable ordering any dish on the menu.
^Contrast that with a situation in which you have a severe peanut allergy, one so severe that you immediately go into anaphylactic shock when you come into contact with even the smallest amount of peanut or peanut oil. If that’s the case, then a mere disclaimer on a menu might not be enough for you to feel comfortable eating in that restaurant.
Perhaps in that case you would need to speak to the restaurant manager, emphasize the severity of your condition, and then double-check to be sure the restaurant really uses no peanut products in their kitchen.
^In the first case, we might say that you would be irrational to continue to ask about the use of peanuts in the kitchen after reading a clear disclaimer on the menu. In the second case, however, nobody would consider you to be irrational if you made absolutely sure that the kitchen didn’t use peanuts or peanut products.
^This seems plausible. And if it’s correct, then it would suggest that whether or not your behavior counts as rational does depend on your practical interests.
Theories of Knowledge LECTURE 22 Pragmatic and Moral encroachment
T he more interest you have in the outcome of a particular question, the more rational it is for you to invest additional time in acquiring more evidence related to the outcome of that question.
^So, if we’re going to block Fantl and McGrath’s argument that practical interests can influence whether or not you have knowledge, we’ll have to block the argument by focusing on the practical condition—the claim that if you have knowledge of some fact, then it’s rational to act as if that fact is true.
^When the practical condition is stated like that, it might seem really obvious. However, there are some good reasons to be skeptical about the practical condition.
] It seems very plausible that many nonhuman animals have knowledge. When a hound tracks a fox to a particular tree, the hound can know that the fox is at that tree.
At the same time, it is not plausible that most of the nonhuman animals that have knowledge are rational;
in other words, the notion of rationality doesn’t really apply to those animals. Rather, it seems plausible to reserve the notion of rationality for creatures who can reflect on their reasons for behaving the way they do. To say
that someone is behaving rationally is at least in part to say that, if the person reflects on his or her behavior, he or she would be able to explain that behavior to him- or herself on the basis of his or her reasons for acting. It’s no disrespect to the extraordinary cognitive abilities of nonhuman animals like dogs to suggest that they are incapable of such reflection. If that’s right, though, then such animals provide examples of creatures who have knowledge but do not act rationally. And if that’s right, then the practical condition is false.
] According to the practical condition, whenever you know something, then that is enough for you to be rational in acting as if it’s true. The problem is that this isn’t true. Sometimes you need more than mere knowledge to have reason to act.
^It seems plausible that there are certain scenarios in which action requires more than mere knowledge.
Sometimes, you have to go above and Theories of Knowledge LECTURE 22 Pragmatic and Moral encroachment
beyond, acquiring evidence greater than what is required for knowledge.
^Think again about the discussion of the menu disclaimer that the kitchen at the restaurant where you’re eating is peanut-free. If the restaurant goes to the trouble of indicating to you that it doesn’t use any peanuts or peanut products in the kitchen, then you can know that the restaurant’s kitchen is peanut-free.
^However, if you have a deadly peanut allergy, it’s totally rational for you to speak to the manager to make absolutely sure that there are
no peanuts or peanut products used in the kitchen. In fact, to go a step further, you shouldn’t eat at that restaurant until you double-check that they really don’t use any peanuts or peanut products in their kitchen.
^If you’re willing to go that far, too, but you accept that the disclaimer in the menu is enough evidence for you to know that there are no peanuts or peanut products used in the kitchen, then you also must reject the practical condition. That’s because this would also be a case in which knowledge alone isn’t sufficient to provide you with reasons to act.