Philosophy Test 3

Introduction to Philosophy

Test #3 Study Guide

Fall 2025

I.          Arguments

Instructions: Please write the premises and conclusions of the following arguments. Where applicable, use the provided brackets to indicate which steps follow from earlier steps.

Argument for Clifford’s Rule

(CR1) It is always wrong, anywhere, for anyone, to believe anything socially significant upon insufficient evidence.

(CR2) Every belief is socially significant

(CR3) Therefore, it is always wrong, everywhere, for anyone, to believe anything upon insufficient evidence.

The Cogito

(C1) Beliefs are based entirely on sense experience

(C2) Deceived by an all-powerful demon

(C3) 

Argument for External World Skepticism

(ES1) If I know I have hands, then I know I am not a BIV.

(ES2) I don’t know I’m not a BIV

(ES3) Therefore, I don’t know I have hands

·  Defense of ES2

(2.1) I know I am not a BIV only if I have evidence that guarantees I am not a BIV

(2.2) I have no evidence

(2.3) I don’t know I’m not a BIV

Moore’s Proof (MP)

(MP1) I have two hands

(MP2) If I have two hands. Then there is an external world

(MP3) Therefore, there is an external world

Moore’s Reply (MR)

(MR1) If I know I have hands, I know I am not a BIV

(MR2) I know I have hands

(MR3) Therefore, I know I am not a BIV

The Genuine Options Argument (GO)

(GO1) No one in a GO has sufficient evidence upon which to believe

(GO2) It 's not wrong for someone in a GO to believe

(GO3) Therefore, it’s not wrong for someone in a GO to believe.

II.        Definitions

Instructions: Please provide precise definitions of the following terms, phrases, and principles. On the test, these will appear in the form of multiple-choice questions.

The JTB Theory: S knows that p if and only if

(i)         S believes that P

(ii)       S’s belief that P is true, and

(iii)     S’s belief that P is justifed

Clifford’s Rule (CR) = “It is wrong always, anywhere, for anyone, to believe anything upon insufficient evidence.

Socially significant belief = A belief that can affect the welfare of someone other than the believer

The Method of Doubt = Try to doubt each belief. If you know you can doubt a given belief, then it isn’t knowledge. But if it can’t be doubted, then it is known with certainty.

Sensory beliefs = beliefs based entirely on sense experience

a priori beliefs = beliefs that aren’t based on sense experience

Dream Hypothesis = I am now asleep in my bed having a very vivid dream

Evil Demon Hypothesis = I’m now being systematically deceived by an all powerful evil demon

Self-Verifying belief  = theory that people actively seek out information and social interactions that confirm their existing self-views, even if those views are negative

BIV Hypothesis = I am a brain in a vat being fed very vivid experiences by a mad scientist’s super computer

External World Skepticism = We know very little to nothing about the external world outside ourselves

Closure = If you know that p entails q, then if you know p then you know that q

Option = “a decision (choice) between two hypotheses”

Live Option = a choice between two live hypotheses

Forced Option = an unavoidable choice between two hypotheses

Momentous Option = a unique choice of great personal significance

Genuine Option = an option that is live, forced, and momentous