I 47/48
Necessary and a priori are not obviously synonymous. They are not even coextensive: there are both: necessary truths from posteriori and probably contingent truths a priori!
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Necessary/Kripke, >
necessary a posteriori, >
necessary de re/Kripke, >
a priori/Kripke.
Many people have thought that these two things should mean the same thing because they imagine we would go through all possible worlds in our minds and then be able to recognize them a priori. But that is not so clear!
I 50
Description: if we call Nixon "the man who won the 1988 election", it will of course be a necessary truth.
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Description/Kripke.
I 66
Prototype meter/standard meter: someone who thinks that everything you know a priori is necessary might think: "This is the definition of a meter. This is a necessary truth." Kripke: however, he/she does not use this definition to specify the meaning, but to define the reference.
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Standard meter, >
Speaker reference, >
Reference/Kripke.
I 68
Rigid: a meter is rigid ((s) "rigid" means that the reference is the same in all possible worlds).
Non-rigid: the length of S at time t is non-rigid.
The "definition" does not say that the two expressions are synonymous, but rather that we have determined the reference of the expression "one metre" by fixing that it is to be a rigid expression of designations, which in fact has the length S. The term "one metre" is not synonymous with the term "one metre". So it is no necessary truth! And that is because under certain circumstances it would not have been one metre long. One expression is rigid and the other is not.
The truth he/she knows is contingent. So I prefer not to call them "analytical."
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Analytic/synthetic, >
Rigidity, >
Contingency.
I 77
E.g. a thesis may be true because it is simply a definition.
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Definition/Kripke.
I 153ff
Reference of proper names:
Definition of the reference: is given a priori (contingent) - this is not the same as synonymy.
Meaning: the meaning is analytical (necessary).
Definition: defines reference and expresses truth a priori.
I 156
E.g. necessary truth: "Cats are animals".
I 175
The phrase "heat is the movement of molecules" expresses a truth a posteriori.
I 181
A posteriori: one can experience a mathematical truth a posteriori by looking at a computer or by asking a mathematician. The philosophical analysis tells us that it was not contingent and therefore any empirical knowledge of its truth is automatically an empirical knowledge of its necessity.
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III 409
Truth/formal languages: understanding the meta language > explicit truth-definition > truth conditions > understanding of the language examined.
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Truth conditions, >
Understanding.
