David Lewis (Modality) Flashcards
What is concrete realism?
The view that possible worlds exist just like this world.
What is modal language?
When we say something could or must be the case.
“Possible worlds are the truth-makers of of modal propositions.” What does this mean?
The fact that possible worlds exist means that modal propositions are made true by their reference to them.
x is possibly true if x is true in some possible worlds
Contingency/Possibility
x is necessarily true if x is true in all possible worlds
Necessity
What does this Lewis quote mean: “an incredulous stare … is not a valid argument.”
Just because the idea seems far-fetched does not make it invalid
“How can one have knowledge of something which is not spacio-temporally related to us?”
What is Lewis’ response to this statement?
Mathematics: we know things about mathematics yet we are not spacio-temporally related to numbers or theorems
For Lewis, why is postulating possible worlds less costly than primitive modality?
Because the ontological cost of concrete worlds is simply adding more tokens of an existing type. Modal concepts are adding another type.
(Ockham’s razor)
“There are no ___ relations at all between things that belong to different ___”
(1) spatiotemporal
(2) worlds
“Are there other worlds that are other ___? I say ___ ___”
(1) ways
(2) there are`
“I advocate a ___ of ___ of worlds”
(1) thesis
(2) plurality
“We make ___ and concepts and descriptions and imaginary ___ that apply to worlds”
(1) languages
(2) representations
“If worlds are causally ___, nothing outside a world ever makes a world”
Isolated
“Because the ___ is serviceable, and that is a reason to think that it is true”
Hypothesis
What is Ockham’s razor?
The law of economy: Things should not be multiplied beyond necessity
