Van InWagen

Handout18.pdf - pdf2html  Annotated

Mereological essentialism: no object can lose or gain parts. In other words,

ME For any t, t

, if x is part of y at t, and y exists at t

, then x is part of y at t

4. Van Inwagen's answer to the Special Composition Question

The xs compose something iff the activity of the xs constitutes a life, or

there is only one of the xs.

What is a life? A certain kind of self-maintaining event, that is `reasonably well-

individuated' and `jealous' (it never happens that the activity of some things

constitutes two different lives).

A consequence of this view: there are no tables or computers or statues or lumps

of clay or ships or grains of sand.... For surely if there was such a things as a

table, etc., it would have to be composed by some things whose activity did not

constitute a life (and which were more than one in number).

Transworld Identity

6.1 Transworld identity and counterpart theory

David Lewis's extreme realism about the nature of possible worlds. The problems in question do not arise directly from the notion of an individual's existing in more than one possible world with different properties. Rather, they derive principally from the fact that it is hard to accommodate all the things that we want to say about the modal properties of ordinary individuals (including all the things that we want to say about their essential and accidental properties) if de re modal statements about such individuals are characterized in terms of their existence or non-existence in other possible worlds.

Untitled

Possible world - Wikipedia, the free encyclopedia  Annotated

David Lewis's defense of modal realism, the doctrine that talk about "possible worlds" is best explained in terms of innumerable, really existing worlds beyond the one we live in. The fundamental question here is: given that modal logic works, and that some possible-worlds semantics for modal logic is correct, what has to be true of the world, and just what are these possible worlds that we range over in our interpretation of modal statements? Lewis argued that what we range over are nothing more nor less than real, concrete worlds that exist just as unequivocally as our actual world exists,

DL rejects AP as not in line with our intuitions of QML

Possible world - Wikipedia, the free encyclopedia  Annotated

reject Lewis's picture as metaphysically extravagant, and suggest in its place an interpretation of possible worlds as consistent, maximally complete sets of descriptions of or propositions about the world, so that a "possible world" is conceived of as a complete description of a way the world could be – rather than a world which is that way. (Lewis describes their position, and similar positions such as those advocated by Alvin Plantinga and Peter Forrest, as "ersatz modal realism", arguing that such theories try to get the benefits of possible worlds semantics for modal logic "on the cheap", but that they ultimately fail to provide an adequate explanation.) Saul Kripke, in Naming and Necessity,

DL rejects how AP has properties

The philosophers' chorus on behalf of ‘trans-world identity’ is merely insisting that, for instance, it is Humphrey himself who might have existed under other conditions, … who might have won the presidency, who exists according to many worlds and wins according to some of them. All that is uncontroversial. The controversial question is how he manages to have these modal properties. (1986, 198)



A natural reaction to Lewis's challenge is to point out that a proponent of transworld identity who is not a Lewisian realist will typically reject Lewis's counterpart theory on the grounds that his counterpart relation does not have the logic of identity

-