Counterfactual Worlds

Abstract

This paper extends Kit Fine’s (2012a, 2012b, 2017a, 2017b, 2017c) truthmaker framework to provide a novel task semantics for tensed counterfactual conditionals. Instead of taking possible worlds to be primitive elements in a model, possible worlds will be defined in terms of states, parthood, tasks, and times where the task relation encodes the possible transitions between states. Rather than invoking primitive relations for similarity or imposition, possible worlds will be compared at a time independent of that time’s past and future where the comparison will be carried out in modal and mereological terms. After reviewing motivations for this approach, I will provide the hyperintensional semantics for counterfactuals that is implemented in the model-checker software along with a unified logic for counterfactual, modal, and tense operators. I will then extend the language to include further tense operators in order to analyze forwards, backwards, and backtracking counterfactuals.