Is man the measure of all things? Or at least, are creatures with subjective internal consciousness the measure of all things? In ancient Greece, the Sophists answered yes. In so doing, they inaugurated Western reflection on a perennial question that stretches throughout both theoretical and practical philosophy, epistemology and ethics.
I’ve briefly discussed this question before, with a focus on ethics. Afterwards, following James Doull, I examined how it gets works out in the history of Western philosophy after the Sophists – in ethics. But as Doull knew, there is an epistemological story that parallels the ethical. God in the Hebrew Bible is the arbiter of truth as well as ethics; the Sophists reduce not merely justice and goodness, but truth, to the subject that knows them. (In a similar way, for Doull, Plato’s Sophist dialogue makes essentially the same point as the Statesman, even though it would appear that one is entirely about metaphysics and the other about politics; both are asking how ideals can relate to physical reality.)
In ethics, as I noted in the earlier post, analytic philosophers tend to use the terms internalism and externalism to describe the opposing positions on this question. In ethics, internalists say that genuine reasons for action must come from our own motivations or desires; externalists say there can be reasons that come from outside us. To use Doull’s examples, the Sophists are the ultimate ethical internalists, the Hebrew Bible the ultimate ethical externalist text. (Consider Ecclesiastes, which repeatedly advises us to fear God and follow his commandments even though it repeatedly denies the possibility of our attaining any benefit for doing so, in this life or the next.)
Now, as well as in ethics, analytic philosophers also use the terms “internalism” and “externalism” to describe positions in epistemology (the theory of knowledge). Ethan Mills discussed this other form of the distinction in comments on a recent post, and I’ve been trying to learn some more about it. What follows is some preliminary attempts of mine to think through the distinction between internalism and externalism in epistemology, and relate it to the distinction in ethics. Apologies if the results are somewhat unclear, as I’m still thinking it through.
Before reading this analytical literature, I had already saw an important internal/external distinction of sorts in epistemology, parallel to the one in ethics. (Doull influenced my thinking here too.) In ethics, we may ask whether we acting subjects are the measure of goodness; just so, in epistemology, we may ask whether we knowing subjects are the measure of knowledge. Ethical internalists say our reasons for action must all come from within us, from our motivations; ethical externalists say we can have reasons to act independent of our motivations. There seems to be a parallel set of questions in epistemology: can the reasons for our beliefs be independent of the ways we come to know them? For example, can we logically speak of a truth that no subject is capable of knowing? Or as the Sophists would put it: is man the measure of truth?
It is not quite clear to me, though, that these questions are what analytic philosophers mean when they speak of “internalist” and “externalist” epistemologies. In Ethan’s comment, the key question dividing internalism and externalism is: Can we really be said to know something if we don’t or can’t know why we know it? Externalists say we can, internalists say we can’t. In online introductory works on internalism and externalism, the problem is phrased in terms of justification rather than knowledge: can our beliefs be justified even in cases where we don’t or can’t know why we hold them?
Now, when the distinction was put in this way, it was not immediately clear to me why these positions were even called “internalism” and “externalism.” In ethics the terminology seems clear enough to me: internalists say that any reasons for action must come from our motivations, which are inside us. But what is “inside us” about knowing how we know or knowing why we hold our beliefs, the hallmark of epistemological “internalism” in the analytic sense? Another article, by Joe Cruz and John Pollock, helped clarify. Internalism on Cruz and Pollock’s view “is the view that all the factors relevant to the justification of a belief are importantly internal to the believer”; our knowing how we know or why we hold our beliefs is itself internal to us. An example of the contrasting, externalist view would be “reliabilism”: the view that a belief is justified if it comes from a source that is in its nature likely to be correct, even if we don’t know that it comes from that source. (So in recent debates “common sense” was defended on the grounds that it is
“reliable.”) The distinction might be illustrated with an example from Laurence BonJour:
Norman, under certain conditions that usually obtain, is a completely reliable clairvoyant with respect to certain kinds of subject matter. He possesses no evidence or reasons of any kind for or against the general possibility of such a cognitive power, or for or against the thesis that he possesses it. One day Norman comes to believe that the President is in New York City, though he has no evidence either for or against his belief. In fact the belief is true and results from his clairvoyant power, under circumstances in which it is completely reliable.
A reliabilist would need to say that Norman’s belief that the President is in New York City is justified, because his clairvoyant power is reliable – even though Norman doesn’t know it’s reliable. (Perhaps it’s one of the first few times the power has manifested.) By contrast, an internalist, like BonJour, says that in such a case Norman’s belief is not justified – even though it’s true. Which is to say, I think, that Norman has no reason to believe the President is in New York.
It’s on this matter of “reasons to believe” that I suspect the two analytical internalism/externalism distinctions dovetail the most. The internalism/externalism question in epistemological justification asks: what counts as a good reason to believe something? In ethics, it asks: what counts as a good reason to do something? In both cases, the internalist says that the good reason must be within us.
Ethan notes in his comments that the South Asian Nyāya school is similar to the reliabilists: what matters is that knowledge is formed by the right kind of process, not anything within us. We can know without knowing how we know. So they are effectively externalists in the analytical sense at issue here. Yet at the same time, the Nyāya have a slogan that “whatever exists is nameable and knowable” – for something to exist objectively, it must be available to subjective knowledge. To speak of something which exists but we couldn’t know – that is meaningless. Here, man (or other subjective knowers) is in some sense the measure of truth, as the Sophists would have wanted to have it. On this score, the Nyāya view seems more comparable to ethical internalism, the view that good reasons must come from within us – truth is in some sense within us knowers as well. Perhaps one could describe the Nyāya as externalists epistemologically, but internalists metaphysically or ontologically?