Street's Darwinian Dilemma

Question 1

What is bayesian confirmation?

Answer 1

a. Consider the relevant data and the competing hypotheses
-it’s critical to know all possible hypothesis
-what is the relative confirmation of the completing hypothesis?
b. For each hypothesis, ask: If it were true, how surprising/weird would this be? [how well does the hypothesis predict the data?]
c. The hypothesis that is most confirmed by the data is the one that makes the data the least surprisn g[the best prediction of the data]
d. To determine how likely each hypothesis is given the data, also factor in prior possibilities
-prior possibilities: the possibilities before you get any evidence –what will be changed

Question 2

What is a good bayesian confirmation? What is an example of this?

Answer 2

A good bayesian confirmation: Would follow the steps about to determine which hypothesis best predicts the data

EX: Say you’re a doctor and a patient tells you their symptoms. You recognize these symptoms as being the same as the common illness, the flu. However, there has recntly been one case of a rare tropicla illness that has the same symptoms of the flu. Despite this, you diagnose the patient with the flu, bbecause the flu is far more common (and the least surprising/weird hypothesis) and matches the evidence and prior possibilities as well.

Question 3

What is a bad bayesian confirmation? What is an example of this?

Answer 3

Bad bayesian confirmation: a process that ignores prior possibilities and picks out the hypothesis that is the most surprising/weird given the data.

EX: A student fails a test and concludes this must be because either a. the test was unfair, or b. the student didn’t study enough. The student claims the test was unfair, but this was a surprising and weird hypothesis to settle on because the student hadn’t studied at all for this test.

Question 4

What is value realism?

Answer 4

there are mind independent facts about goodness and badness.

Question 5

What is Street’s argument?

Answer 5

1. The content of our value intuitions are heavily influenced by naturual selection.
   a. we know this because it has a high prior probability because our value intuitions affect actions that will affect surivial and reproduction
   b. the value intentions we have are what we’d expect if naturual selection influenced them
   c. we can see some of our value intentions in our ancestors, which we would expeect/predict if these were influenced by natural selection.
2. If naturual selection for these intuitions, this is either because i.) they were adaptive because they were true, or ii.) they were adaptive whether or not they were true.
3. Hypothesis i.) is less plausible than hypothesis ii.)
   a. Hypothesis ii.) is more parsimonious (more simple)
   b. Hypothesis ii.) predicts and explains the data best
   c. This is where Vavova disagrees with Street
4. So, most plausibly, our value intuitions were selected for because they were adaptive, whether or not they were true
5. So, if our value intuitions are reliable, and value realism is true, this reliability is a massive coincidence
   a. it could easily be that our intuitions were not reliable
   b. it is an accident that our intutions track real value facts
6. Thus, if value realism is true, evolution defeats the justification for balue belief (if realism, then defeat)

Summary:
-our value intentions are influenced by naturual selection
-it is more likely that these value intentions were selected randomly (whether or not they were true)
-if value intuitions are reliabile (and value realism is true), then this is just a coincidence
-so, if value realism is true, evolution poses as an UNDERCUTTING defeater for the justification of value belief.

Question 6

How does Street’s argument relate to other things we’ve read?
-Is it a problem for moral knowledge given PC? Process reliabilism? How/why?
-How does it relate to convergence and divergence, or to consistency??
-How might Alston reply to Street?