Vogel, Skepticism and Inference to the Best Explanation. Flashcards
What is the Deceiver Argument in skepticism?
It’s a 3-part argument that concludes we have no knowledge of the external world:
- Our sensory experiences could arise either from real perception or massive deception.
- We have no reason to favor one source over the other.
- Therefore, we have no knowledge of the external world.
What principle supports the conclusion of the Deceiver Argument?
The Underdetermination Principle—if two hypotheses are equally supported by the evidence, and we have no reason to prefer one, then we do not know either to be true.
What is the philosophical challenge posed by premise (2) of the Deceiver Argument?
It claims we have no reason to believe our experiences are veridical rather than deceptive, leading to global skepticism unless this premise is rejected.
What is the Moorean response to skepticism?
Named after G.E. Moore, it asserts that sensory experience itself justifies belief in the external world, and thus provides a reason to deny deception.
How does the Moorean try to refute premise (2)?
By arguing that, for example, the experience of seeing a tree justifies the belief that there is a tree—and this implies that one is not being deceived.
What is the major critique of the Moorean strategy?
It’s circular—like trusting a fuel gauge based solely on its reading to confirm its accuracy. You can’t use the output of a potentially deceptive system to prove the system isn’t deceptive.
What is the a priori approach to denying premise (2)?
It argues that belief in the reliability of perception is rationally necessary—perhaps a precondition for rationality itself—rather than justified by experience.
What problem arises with the a priori approach?
It lacks clear justification—reason alone seems inadequate to determine the actual causal source of our sensory experiences (e.g., computer vs. tree).
What is inference to the best explanation (IBE)?
A method of reasoning where we accept the hypothesis that best explains the available evidence and reject inferior explanations.
How does Vogel use IBE to counter skepticism?
He argues that the real world hypothesis (i.e., what we believe is true) explains our experiences better than skeptical alternatives do. Thus, we are justified in believing it.
What does the “real world hypothesis” entail?
That the external world exists more or less as it seems, and that our sensory experiences are caused by interaction with real objects (e.g., seeing a tree because a tree is there).
What is a minimal skeptical hypothesis?
A bare assertion that your experiences are unveridically caused, without explaining how or why. It’s vague and offers no detailed causal mechanism.
Why is the minimal skeptical hypothesis weak?
It’s ad hoc—it offers no explanatory power and is like saying “something else did it” without further detail. Such theories are inferior to well-supported explanations.
What is the isomorphic skeptical hypothesis?
A detailed skeptical theory claiming that each of your experiences is caused by a computer simulation that mimics the external world exactly, but isn’t actually what it represents.
How does Vogel critique the isomorphic skeptical hypothesis?
Although detailed, it’s more complex and convoluted than the real world hypothesis. For example, explaining a “round peg” requires simulating roundness without real roundness—making it less parsimonious.
What makes an explanation better in IBE?
Simplicity, coherence with other beliefs, and explanatory power. A good hypothesis explains the data without unnecessary complexity.
What is Vogel’s final stance on skepticism?
That premise (2) of the Deceiver Argument is false, because the real world hypothesis is explanatorily superior to skeptical hypotheses. Thus, the skeptical argument fails.
How does Vogel use the Flat Earth example?
He compares the isomorphic skeptical hypothesis to the Flat Earth theory: both require unnecessarily complex assumptions to account for familiar phenomena, unlike their simpler rivals (Round Earth, real world hypothesis).
Why does Vogel think explanationism solves skepticism?
Because it justifies belief in the external world through rational inference—not blind assumption—by showing that skeptical alternatives are inferior explanations.
