Presenter Jannai
Note Taker: Andrew
Demystifying Underdetermination
Goal: to show that underdetermination founder because they suppose that the logically possible and
the reasonable are coextensive.
Underdetermination: Evidence is insufficient to justify beliefs and will never tell you the exact theory
you should hold no matter what or how much you have. It is reasonable to accept a theory that is logical
with the evidence, and there are infinite theories that can be made to fit the evidence.
Polanyi, Wittgenstein, Feyerbend: “Science has no rules”
Underdetermination does not accept epistemic rules
Epistemic rules: a rule for judging a theory based on some aspect other that its logic. Ex. Elegance,
simplicity
Humean underdetermination: HUD
Luke: do the underdetermanist’s ideals apply to only one specific instance of evidence for a theory or do
their oppositions apply to all strings of evidence? Do you have HUD once you have more than one piece
of evidence.
= three theories that explain the same data
HUD is weak on two counts: only uses deductive logic, and does not say that all theories are equally
reconcilable, but that infinitely many are. It does not establish that all theories are equally good.
Quinean Underdetermination: QUD
Non uniqueness thesis
Egalitarian thesis
Ampliative inferences: anything that does beyond straight contradiction. Ex. choose the most elegant,
inductive
Quine fails in his argument: even if he could prove there are some ampliative rules that are no good, it
would not prove that all are no good.
Critiques of Popper: you don’t reject a theory by falsifying instances; only the “web of belief” is falsified.
Nothing in the web can be isolated
Luke: can you test an axillary hypothesis?
Problem: you will always be making theoretical commitments and there are always a set of auxiliary
hypothesis that can replace those that are held. Quine fails to prove these auxiliary hypotheses exist.
Say you have “sixed” you web of belief after it has been proven incorrect. According to Quine, there is
no reason to accept either and Lauden is asking what is his justification for such a claim. Lauden says just
because it is possible does not mean it is reasonable.
Luke: Why do we assume nature is simple and can be explained by simple theories? Is this a
metaphysical assumption and is it reasonable?
Simplicity is an ampliative inference/ metaphysical assumption.
Anton: there may be different types of simplicity
Ross: is simplicity a pragmatic argument?
Jannai: is it more rational to accept a more elegant theory
Sansom: do we naturally try to simplify things due to social, evolutionary, or some other type forces.
Ampliative Underdetermination:
Goodman: 1 rules of ampliative underdetermination has defect. It is inductive
Grue: having a characteristic until a certain time where that characteristic changes. Green now until it is
blue. Grue/ green are equally good theories.
Kuhn: paradigm shifts are not always justified by the data/ experience. Paradigms are supported by their
own standards and discredited by the standards of others. There are other factors that contribute to the
acceptance of a theory.
Kuhn does not give an argument that establishes the ambiguity of theory choice.
Kuhn says that you always have got scientific reason to hold onto a theory and Lauden says tou can only
feel that way if you are an egalitarian.
KEY IDEA
Pay attention to the details because it is within them that the argument is made.
Underdeterminationists will justify a lesser underdeterminationism as justification for their own more
extreme views.
Lauden gives an\ example of an instance where a theory was rejected over another
He has not discredited all underdetermination nor has he given a way to do about choosing.