SLIDE 1
Probabilis3c Frames
- W is a set of possible worlds.
- P is a func3on mapping world w to
Comments for: Two Cheers for Akrasia by Kevin Dorst Konstan3n Genin - - PowerPoint PPT Presentation
Comments for: Two Cheers for Akrasia by Kevin Dorst Konstan3n Genin - - PowerPoint PPT Presentation
Comments for: Two Cheers for Akrasia by Kevin Dorst Konstan3n Genin Carnegie Mellon University 2018 Eastern APA Savannah, Georgia Probabilis3c Frames W is a set of possible worlds . P is a func3on mapping world w to P w, the uniquely
SLIDE 2
SLIDE 3
Probabilis3c Frames
We want to talk about what credences you ought to have: In English: `one (you) ought now to be t- confident of p.’
[P(p) = t] := {w : Pw(p) = t}
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Probabilis3c Frames
For this setup to make sense it must be that the total evidence is a func3on of the world. Let Ew be the set of worlds compa3ble with the total evidence in w.
SLIDE 5
Worlds = infinite sequences of coin flips. Eviden1al states = cones of possible extensions of finite sequences:
Standard Sta3s3cal Setup: Sequen3al Binary Experiment
- bserved so far
SLIDE 6
Higher-order Uncertainty
Kevin argues that the following situa3on is ra3onally permissible:
- and
- Pw 6= Pw0
Pw(w0) > 0.
SLIDE 7
Eviden3al Internalism
- Internalism: If E is your total evidence, then it
entails that it is your total evidence:
- Externalism: Some3mes your total evidence
does not entail that it is your total evidence. Gallow (2017)
Ew ⊆ {w0 : Ew = Ew0}.
SLIDE 8
The Internalist Argues against HoU
- 1. If then
- 2. If then (Internalism).
Ccl.
Pw 6= Pw0 Ew 6= Ew0. Ew 6= Ew0
{w0} ∩ Ew = ∅ Pw(w0) = 0.
SLIDE 9
Dorst denies Eviden3al Internalism
Kevin argues for higher-order uncertainty by producing examples in which eviden3al internalism seems to fail.
SLIDE 10
¬p
Bianca the Biologist
p
If the sample is poisonous, Bianca will eventually verify that it is. If the sample is safe, she will never be able to verify that it is safe.
SLIDE 11
The Internalist Response
If total evidence is a feature of the world, then so is what evidence you have managed to figure out by now.
SLIDE 12
Bianca the Biologist
p, r p, r p, r
Whether or not Bianca has realized that the sample is poisonous is now a feature
- f the world.
SLIDE 13
Bianca the Biologist
p, r p, r p, r
Total evidence now sa3sfies eviden3al internalism.
SLIDE 14
Suppose there are at 0-2 possible comple3ons of the word fragment. 1
2
Word Comple3on
SLIDE 15
(1,0) (2,0) (0,0)
How many comple3ons I’ve thought of is part of the world.
(1,1) (2,1) (2,2)
Word Comple3on
Number of Comple3ons Number I’ve thought of
SLIDE 16
(1,0) (2,0) (0,0)
Eviden3al internalism is sa3sfied.
(1,1) (2,1) (2,2)
Word Comple3on
Number of Comple3ons Number I’ve thought of
SLIDE 17
Peer disagreement
The situa3on Kevin describes could be modeled in two different ways.
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