Necessarily, a being has maximal excellence in every world only if it has omniscience, omnipotence, and moral perfection in every world.Necessarily, a being is maximally great only if it has maximal excellence in every world.There is a possible world in which maximal greatness is instantiated.Īnd the analogues of (27) and (28) spell out what is involved in maximal greatness:.Plantinga stated his final argument thus: As Plantinga admitted, 'I am inclined to think the supposition that there are such things-things that are possible but don't in fact exist-is either unintelligible or necessarily false.' I will try to show below that even with the expunction of this ontologically questionable entity, Plantinga's final, revised argument fails. He believed that there were too many inherent problems with this concept. The last Achilles' heel he had designed to avoid was the argument's reliance on the concept of possible beings. He examined each in succession, discarding them as he proceeded while repairing the weaknesses of each until he arrived at what, he claimed, is the final triumphant version. Plantinga progressed through a number of versions of his ontological argument. (For a substantive critique of Plantinga's more technically stated version given in his The Nature of Necessity, see Mackie.

For the purposes of this essay, I will focus on Plantinga's formulation of his argument in his God, Freedom and Evil. I will rest content if I succeed in showing that Plantinga's attempt to appraise an existential proposition about what exists through the use of 'possible world' semantics cannot hope to succeed. I will avoid discussion of controversial problems, such as transworld identity, because I do not think this is necessary for the purpose of this critique. Debate about the meaning and significance of possible worlds to the discipline of modal logic remains current among philosophers. Since Leibniz first coined the term, 'possible world', in the seventeenth century, it has gained widespread attention. Here, Plantinga attempted to use the philosophical concept of possible worlds to show the necessary nature of God's existence. Plantinga developed his modal version of the ontological argument for the existence of God in his two controversial books, The Nature of Necessity and God, Freedom and Evil.

Alvin plantinga the nature of necessity