#### Conference Level

Graduate

#### Location

University of Windsor

#### Start Date

28-3-2015 2:00 PM

#### End Date

28-3-2015 2:30 PM

#### Abstract

Abstract: Incompatibilism is the philosophical view, according to which, free will is incompatible with determinism. Van Inwagen in his paper “A modal argument for incompatibilism”, presents one of the most compelling arguments in favor of the view by showing that, if we don’t “have a choice about whether” determinism is true nor do we “have a choice about whether” the proposition representing the past and the conjunction of the laws of nature is true, then necessarily we don’t “have a choice about whether” any future description of the world is true. Even though most of the premises of the modal version of the argument have received a lot of critical attention in the literature and Van Inwagen himself has taken great pains to defend them, the first premise of the argument regarding the definition of determinism (□ (P_{0} & L) → P) is considered to be uncontroversial. The goal of my paper is to challenge the first premise by a) offering two possible interpretations of determinism that could correspond to the modal version of the premise, and b) developing strategies on how the defender of compatibilism could refute the premise under each interpretation. According to the first interpretation, the premise “□ (P_{0} & L) → P” is equivalent to the proposition “*Necessarily*, the past and the conjunction of the laws of nature entail the future”, which could be refuted by showing that determinism is an empirically contingent thesis tightly correlated with the success of scientific predictability and thus its logical consequences could only be empirically contingent as well. According to the second interpretation, the premise “□ (P_{0} & L) → P” is equivalent to the proposition “The past and the conjunction of the laws of nature *logically* entail the future”, which could be true only if every proposition describing a future state of the world was *logically* equivalent to the consequent of some law of nature. Propositions describing future free-willed human decisions employ sociopsychological terms that are irreducible to the natural kind predicates of neuroscience. Therefore, the first premise fares no better under the second interpretation than under the first one.

Van Inwagen's modal argument for incompatibilism

University of Windsor

Abstract: Incompatibilism is the philosophical view, according to which, free will is incompatible with determinism. Van Inwagen in his paper “A modal argument for incompatibilism”, presents one of the most compelling arguments in favor of the view by showing that, if we don’t “have a choice about whether” determinism is true nor do we “have a choice about whether” the proposition representing the past and the conjunction of the laws of nature is true, then necessarily we don’t “have a choice about whether” any future description of the world is true. Even though most of the premises of the modal version of the argument have received a lot of critical attention in the literature and Van Inwagen himself has taken great pains to defend them, the first premise of the argument regarding the definition of determinism (□ (P_{0} & L) → P) is considered to be uncontroversial. The goal of my paper is to challenge the first premise by a) offering two possible interpretations of determinism that could correspond to the modal version of the premise, and b) developing strategies on how the defender of compatibilism could refute the premise under each interpretation. According to the first interpretation, the premise “□ (P_{0} & L) → P” is equivalent to the proposition “*Necessarily*, the past and the conjunction of the laws of nature entail the future”, which could be refuted by showing that determinism is an empirically contingent thesis tightly correlated with the success of scientific predictability and thus its logical consequences could only be empirically contingent as well. According to the second interpretation, the premise “□ (P_{0} & L) → P” is equivalent to the proposition “The past and the conjunction of the laws of nature *logically* entail the future”, which could be true only if every proposition describing a future state of the world was *logically* equivalent to the consequent of some law of nature. Propositions describing future free-willed human decisions employ sociopsychological terms that are irreducible to the natural kind predicates of neuroscience. Therefore, the first premise fares no better under the second interpretation than under the first one.