A while back, in an attempt to assuage feelings of doubt, I wrote a post on why the main issues in epistemology matter to Joe and Joanne Shmo. Here, I will address why what appears to be an insignificant esoteric and abstract issue in epistemology has extremely important consequences to our daily lives and especially our social institutions.
Before reading what I have written click on the link and watch the video:
I said click it!
Ok, so if you didn't have a chance to watch the entire video here is the most relevant point:
72% of wrongful convictions that are later overturned by DNA evidence are a result of eyewitness testimony.
Let's get the terminology out of the way. Epistemology is the study of knowledge. Two of the major questions that are explored in epistemology are (a) what is knowledge? (b) what is it possible to know? (i.e., what are the limits of knowledge). Apart from these central issues, there are other important issues one of which I mentioned before: when is a belief justified?
It shouldn't come as a surprise to any thinking person that some beliefs are well-justified and others are not so much--or not at all. So, when is a belief justified and when isn't it? Establishing some rules or principles for justification before we go out into the world will allow us to avoid falling prey to ideas and beliefs that might be appealing (i.e., confirm our biases) yet are not well-supported.
Consider Jennifer Thompson's testimony. Pretty convincing right? She has pretty convincing support for her belief about who raped her. If you think that the reasons she cites for her beliefs are strong justification then you are subscribing to a theory of justification called internalism or "current time-slice" theory.
Don't be scurd by the fancy name. All this means is that for a belief to be justified, the believer or proponent has to, in principle, be able to--at the moment of inquiry--produce some sort of compelling evidence or support for their belief. Otherwise stated, a justifying reason for the belief must be internally accessible to the believer. In Jennifer's case, maybe it's a memory or are current observation. Justification for moral beliefs might be an appeal to a commonly held moral principle, for a scientific belief it might be an observation or an inference. Regardless, the main point of internalism is that the justification for a belief must be accessible to and produceable by the believer.
An externalist on the other hand says that justification has nothing to do with conscious access to reasons and everything to do with the reliability of the process by which the belief was acquired. "Reliability" in this context means "the process by which the belief was acquired produces more true beliefs than false beliefs over the long run." The externalist or "process reliabilist," as they are sometimes called, doesn't care two hoots about the justifying reasons to which Jennifer has conscious access. They only care about whether the process (eye-witness testimony, in this case) by which Jennifer acquired her beliefs produces more true beliefs than false beliefs in the long run (i.e., that the process is reliable).
Now, lets consider Jennifer's testimony from the point of view of an externalist. We know that the process of eye-witness memory and testimony is unreliable, in fact, it's very unreliable. We know that in the long run, more beliefs that are formed from these processes will turn out to be false than they will turn out to be true. So, if we adopt an externalist model of justification, we ought to reject Jennifer's testimony. It isn't a justified belief.
Adopting process reliablism as our theory of justification tells us we ought to focus our attention on the reliability of processes rather than reasons. In the video clip we learn of all the different ways in which the (current) process of eye-witness testimony can fail and how it might be corrected. It seems counter-intuitive to say we should dismiss Jennifer's testimony, however, by focusing on processes rather than reasons as justification, we can avoid tragic errors.
Our preferred philosophical theory of epistemic justification has huge practical implications in many domains, and it is made most readily apparent in the court of law. As a thought experiment, think about the practical consequences to your area of expertise of applying one theory of justification vs another. You'll likely find there are important consequences.
Epistemology matters--and not just to philosophers. The theory of justification we choose can have implications as to whether people are likely to wrongfully convicted.
Boom goes the dynamite.