Analysis Of Robert C. Stalnaker's 'Possible Worlds'

Introduction
The following essay is based on the paper „Possible Worlds‟ by Robert C. Stalnaker from Cornell University. The author Robert C. Stalnaker is probably best known as one of the founders along with David Lewis of the possible world theory of conditionals and counterfactuals. Stalnaker takes the possible world framework as a method to look at some problems in the theory of knowledge and philosophy of mind.
In this paper, the author recognises four theses in what he calls David Lewis‟s extreme realism about possible worlds. The author explains the reasons which made him disagree with this extreme realism of David Lewis. Stalnaker advocates what he calls moderate realism which is essentially carefully revised version of extreme realism.
However, possible worlds failed to gain any real traction among philosophers until the 1960s when they were invoked to provide the conceptual foundations of some powerful developments in modal logic. „Possible World‟ has been part of the philosophical lexicon since Leibniz. The notion became firmly entrenched in contemporary philosophy with the development of possible world semantics for the languages of propositional and first-order modal logic. Leibniz described the universe- the actual world-is one of an infinite number of possible worlds existing in the mind of God. According to him, God actualised the best possible world as the universe. This paper has been of utmost importance for the thorough understanding of possible worlds. This paper also focuses on propositions which are simply ways of distinguishing between possible worlds and they are useful for characterising and expressing an agent's attitudes toward those possibilities. The roots of this paper lie in disagreement between the points proposed by David Lewis and Robert C. Stalnaker, (two notable names in the world of philosophy). Hence this paper is of extreme significance for those who want to understand the concept of Possible World
ways things might have been. What are those possible worlds? Stalnaker argues in favour of a moderate realism with respect to these things. Possible worlds are conceived just as real as the actual world though, they do not actually exist. Because "actual" is indexical, 'like "I" of "now", it depends for its reference on the circumstances of utterance. Moderate realism denies however, unlike the extreme realism of David' Lewis, that the entities of those possible worlds are concrete particulars or at least entities which are made up of concrete particulars and events. Possible worlds, says -Stalnaker, are not concrete objects or situations, 'but abstract objects whose existence is inferred or abstracted from the activities of rational agents. The nature of possible worlds is left