phil 2303 phil intro to logic truth what

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phil 2303 phil intro to logic

phil 2303 phil intro to logic

? truth? what is

? truth? what is

three 'truth' theories

three 'truth' theories

pragmatictheory of truth

pragmatictheory of truth

a statement is true if it allows you to interact effectively and efficiently with

a statement is true if it allows you to interact effectively and efficiently with the cosmos. the less true a belief is, the less it facilitates such interaction. a belief is false if it facilitates no interaction. in simpler terms: a belief is true if it actually 'works'

william james

william james

example: my belief that inanimate objects do not spontaneously get up and move about

example: my belief that inanimate objects do not spontaneously get up and move about is true because it makes my world more predictable and thus easier to live in.

counter example/argument: an isolated indigenous tribe might believe that human sacrifice brings their crops

counter example/argument: an isolated indigenous tribe might believe that human sacrifice brings their crops back each year. The crops do come back after the human sacrifice, but not because of the human sacrifice. .

coherencetheory of truth

coherencetheory of truth

a statement is true if it is logically consistent with other beliefs that are

a statement is true if it is logically consistent with other beliefs that are held to be true. a belief is false if it is inconsistent with (or contradicts) other beliefs that are held to be true. in other words: we should doubt claims that are currently inconsistent with the rest of our beliefs

willard quine

willard quine

example: we don't believe in solipsism because it contradicts many of our others sacredly

example: we don't believe in solipsism because it contradicts many of our others sacredly held beliefs.

counter example/argument: the universe came into existence five minutes ago complete with historical records

counter example/argument: the universe came into existence five minutes ago complete with historical records and memories

correspondencetheory of truth

correspondencetheory of truth

a claim is true if it corresponds to what is actual (the "facts" or

a claim is true if it corresponds to what is actual (the "facts" or "reality") and false if it does not correspond to what is so. in other words: my beliefs are true if they reflect the way the world really is.

bertrand russell

bertrand russell

example: the statement: 'the opera Aida had its first performance in Cairo' is true

example: the statement: 'the opera Aida had its first performance in Cairo' is true just in case the opera Aida had its first performance in Cairo, and false otherwise. "snow is white" is true just in case snow is white.

counter example/argument: does the correspondence theory of truth (itself) correspond to the way the

counter example/argument: does the correspondence theory of truth (itself) correspond to the way the world really is, if so- how?

Readingassignments {Pirie text} 'ad baculum' arguments page 17. 'ad hominem' arguments page 88. 'ad

Readingassignments {Pirie text} 'ad baculum' arguments page 17. 'ad hominem' arguments page 88. 'ad misericordiam' arguments page 109