Abstract

I assess the thesis that counterfactual asymmetries are explained by an asymmetry of the global entropy at the temporal boundaries of the universe by developing a new semantic element for counterfactuals called objective assertibility and a method of evaluating counterfactuals that constrains consideration to possibilities where the early universe has low entropy. The resulting theory vindicates the common practice of holding the past mostly fixed under counterfactual supposition while at the same time allowing the counterfactual's antecedent to obtain by a natural physical development. While excellent for evaluating a wide variety of ordinary counterfactuals, it does not fully succeed as an explanation of counterfactual asymmetry