Tense Forms of Moore's Paradox

Moore’s sentences are sentences of the form “p but I don't believe that p” or “p but I believe that not-p”. These sentences are called the omissive and the commissive form of Moorean sentence, respectively. These sentences might be true, yet they are ‘absurd’ to believe. It is usually claimed that absurdity only occurs when these sentences are formulated in the present tense, but if they are expressed in the past tenses or future tenses they would not be absurd. In this paper, we will analyze the Moore’s sentences in various tenses: past, present, and future. In this respect we employ a logic which is a combination of hybrid tense logic and doxastic logic. Then by formalizing the Moore’s sentences in various tenses we show that, contrary to popular belief, the past and future versions are not necessarily absurd. Finally, we give a necessary and sufficient condition for determining the absurdity of the Moore’s sentences