Do Logical Aliens Think? Frege’s Agent-Relative View of Logic’s Constitutive Role for Thinking

Abstract Must you respect basic logical laws (BLL) – such as the law of non-contradiction – in order to think? Frege wrote that one must “acknowledge” BLL in order not to “abandon judgement altogether”. Some have argued that Frege therefore thought of logic as somehow ‘constitutive’ of thinking. However, some interpreters contend, due to his strong commitment to logic’s normative status, that Frege held the opposite view, namely the non-constitutivist view that (systematic) ‘illogical’ thinking is possible and that one need not accept or follow BLL in order to think as such, although one must do so in order to think correctly. The aim of this paper is to investigate the interpretative landscape regarding Frege’s view on logic’s constitutive role for thinking and suggest, against the non-constitutivist readings, that he indeed was committed to some version of the constitutivity thesis, but that this commitment is not, as some constitutivist interpretations suggest, inconsistent with the idea that logic is normative for thinking. I will, instead, propose to read his view in a soft and agent-relative sense, according to which it is a necessary condition for the possibility of thinking that the agent in question is sensitive to and acknowledges BLL.