American Catholic Philosophical Quarterly

Volume 97, Issue 1, Winter 2023

A Correction to Dillard’s Reading of Geach’s Temporality Argument for Non-Materialism

In his article “What Do We Think With?” Peter Geach develops an argument for the non-materiality of thinking. Given that basic thinking activity is not clockable in physical time, whereas basic material or bodily activity is so clockable, it follows that basic thinking activity is non-material. Peter Dillard’s attack on this temporality proof takes “thoughts” in the proof to refer to non-occurrent states. The present note shows this reading to be mistaken and so rectifies a misunderstanding of Geach’s argument. It takes no stand on the question of whether the argument succeeds.