The two major hypotheses
Much of this class will be devoted to considering two major, mutually exclusive hypotheses concerning the JFK assassination:
I. JFK was killed by a single gunman acting alone.
II. JFK was killed by a conspiracy.
The possible results for each hypothesis are:
(a) Retain it.
(b) Reject it.
You reject a hypothesis by falsifying it. If you can't falsify it, you automatically retain it. To understand the idea of falsifying a hypothesis, see the seminal essay by Sir Karl Popper entitled "Science, Pseudo-science, and Falsifiability."
As we go along, we will see that the lone-gunman hypothesis (I) can easily be falsified, but that the conspiracy hypothesis (II) cannot be falsified (because you can never truly prove that someone worked alone). This introduces an interesting asymmetry to our considerations, and makes it very important to think a little more deeply about dealing with hypotheses. We will even consider the epistemology appropriate to the JFK assassination.
In connection with the conspiracy hypothesis, we will be considering why there remains such a wide range of conspiracy theories, even after 36 years. (See Two Defining Questions.) We will also deal with the next question, of why conspiracy remains such a popular explanation for the crime even though no one can say definitively who the conspiracists were. Can you ever prove conspiracy without knowing the conspirators? I suspect that the answer is yes, but it gets murky fast. In any event, we will see how close the evidence comes to proving conspiracy. We will also think about what one does when many pieces of important evidence are uncertain or missing altogether, as is the case here.