On the problem of ontology and epistemology of the possible worlds

One of the central concepts in modern semantics of a number of non-classical logics (primarily, modal) is the possible worlds concept. It is believed that history of using this concept goes back at least to the Leibniz philosophy, who used it to distinguish between the so-called truths of reason and the truths of fact. It should be noted that truths of reason were defined as taking place in all the possible worlds (logically consistent situations), and truths of fact — as taking place only in some of them. Unfortunately, modern interpretation of this concept does not have the same degree of obviousness. When constructing semantics of this type, the concepts of relative possibility (reachability) between the worlds and the model structure are used; these concepts are of a purely formal nature and require additional interpretation. The situation is complicated by the fact that the idea of alternative worlds is quite popular in modern physics. In this regard, the problem arises of clarifying ontological status of the possible worlds, as well as a clear distinction between philosophical and natural scientific interpretations of this concept. The article proposes a solution to certain indicated problems.

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