As stated in W11 Slide #36, the Principle of Indifference says:
When faced with n > 1 possibilities that are mutually exclusive and jointly exhaustive, and you have no evidence about their relative likelihoods, a probability equal to 1/n for each possibility.
I also gave two examples in the lecture:
Paul graduated from either JPJC, ACJC, or SAJC (and exactly one of them), but you don’t know which and you don’t know the likelihood of him going to any one of them.
Assign a probability equal to 1/3 to the possibility that he went to SAJC.
You have one lucky draw coupon, and you know that one coupon from a pile (numbered 000,000,000 to 999,999,999) will be picked. Each coupon give you one chance of willing. Assign a probability equal to 1/1,000,000,000 to the outcome where your coupon is the winning coupon.
Now, the “probability” we are talking about is not something about the world–about where Paul actually went to school, or which coupon is the actual winning coupon. Rather, we are talking about the level of confidence you shouldhave, if you are being rational, in one of the options being true, given that you don’t know yet.
Small edits made to the question. Ok, some of you seem to be getting lost in the story. I’ll put the below down to help you.
Scenario in Abe’s Statements
Lena is religious, privy to religious experiences, her experiences count as evidence for the existence of God, believes that God exists;
Will and Gene are not religious, not privy to religious experiences; Will believes that God doesn’t exist (while Gene believes that God exist);
Evaluate: Given the above, and the concepts taught, is it correct that–Epistemic Uniqueness is true in the disagreement between Lena vs Will over whether God exists, because the scenario shows that both Lena and Will can never have the same evidence, and if they can never have the same evidence, their opposite but equally justified beliefs can never be rationally based on the same evidence?
Scenario in Dave’s Statements:
The Scenario in Abe’s Statements, plus:
Lena’s testimony also count as good evidence for God’s existence; she told both Will and Gene about her experiences;
Will and Gene are equally smart and have thought equally hard about God’s existence;
Evaluate: Given the above, and the concepts taught, is it correct that–the Epistemic Permissivist who says that Will and Gene are equally justified in their own beliefs (on the same evidence) would be begging the question against both of them.
Scenario in Tess’ Statements:
Same set up as in Dave’s Statements.
Evaluate: Given the above, and the concepts taught, is it correct that–If someone agrees that the disagreement between Gene and Will (based on the same evidence) can never be resolved in such a way that both Gene and Will are equally justified, then this person cannot also consistently subscribe to Epistemic Permissivism?
Update: A couple more came in later and I’ve included them. Look for those with the “[Added]” marker.
Is epistemology descriptive with a prescriptive edge?
A big part of it is prescriptive. Like morality, rationality involves an evaluative dimension–just as there are such things as good or bad, right or wrong with it comes to action, there are also rational or irrational, justified or unjustified, true or false, etc., when it comes to beliefs.
I wrote the below back when the knowledge topic dealt with the regress argument for justification (the very first semester I took on teaching GET1029, by the way). It also touches on issues relating to how we respond to skepticism. Since a couple of you asked, I’ll make it available here for those interested.