Ideas from 'The Nature of Necessity' by Alvin Plantinga [1974], by Theme Structure

[found in 'The Nature of Necessity' by Plantinga,Alvin [OUP 1982,0-19-824414-2]].

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10. Modality / E. Possible worlds / 1. Possible Worlds / d. Possible worlds actualism
Plantinga says there is just this world, with possibilities expressed in propositions
                        Full Idea: Plantinga rejects other possible worlds, but adds to our world an uncountable multitude of sets of propositions, each set a way that the world might have been, but is in fact not. (Roughly, for each Lewis world, Plantinga has such a set).
                        From: report of Alvin Plantinga (The Nature of Necessity [1974]) by David M. Armstrong - Truth and Truthmakers 07.2
                        A reaction: To me it seems as ontologically extravagant to postulate unexpressed propositions as to postulate concrete possible worlds. I think the best line is that there is just the actual world, with the possibilities implied in its dispositions.
10. Modality / E. Possible worlds / 3. Transworld Objects / b. Rigid designation
Possibilities for an individual can only refer to that individual, in some possible world
                        Full Idea: Plantinga says for an individual to exist with certain properties in some possible world is simply for it to be true that, had that possible world obtained, that individual would have existed with those properties.
                        From: report of Alvin Plantinga (The Nature of Necessity [1974]) by Penelope Mackie - How Things Might Have Been 5.1
                        A reaction: This is intended to dissolve the problem of transworld identity, and is certainly a flat rejection of counterparts. I take the point to be that the individual is the key element in defining the possible world, so can't possibly be different.
28. God / B. Proving God / 2. Proofs of Reason / a. Ontological Proof
A possible world contains a being of maximal greatness - which is existence in all worlds
                        Full Idea: Plantinga reformulates Malcolm's argument thus: 1) There is a possible world in which there exists a being with maximal greatness, 2) A being has maximal greatness in a world only if it exists in every world.
                        From: report of Alvin Plantinga (The Nature of Necessity [1974], p.213) by Brian Davies - Introduction to the Philosophy of Religion 4 'b Descartes'
                        A reaction: This is only Plantinga's starting point, which says nothing about the nature of God, but only that this 'great' being exists in all worlds. I would like to know why it is a 'being' rather than a 'thing'. Malcolm says if it is possible it is necessary.