Abstract

Rationalists like Bealer (1999), BonJour (1998), and Plantinga (1993) hold there are conscious intuitions that supply a priori justification. Peacocke (2021) and Marasoiu (2020) point out that this raises a Problem of Arbitrariness: Why are beliefs justified by rational intuitions a priori, if rational intuitions are phenomenally conscious experiences, when other beliefs justified by experience are not a priori? I point out that the real issue for rationalists isn’t whether intuitions supply ‘a priori’ knowledge or justification, but whether they supply knowledge or justification for necessary synthetic propositions. Such knowledge is what rationalists, but traditionally not empiricists, are really after. In answering the Problem of Arbitrariness by highlighting the necessary synthetic, these rationalists should commit to non-sensory or irreducibly cognitive phenomenology. For conscious intuitions that have merely sensory phenomenology cannot (re)present and justify the necessary synthetic propositions that rationalists are after. But these rationalists say such intuitions have some phenomenology. So their only recourse is to believe in non-sensory, cognitive phenomenology. I then offer reasons for such rationalists to prefer an acquaintance model of rational intuition: it explains why cognitive phenomenology must be present in experiential justification of the necessary synthetic, and differentiates phenomenal rationalism from recent versions of empiricism, which also accept justification of the necessary synthetic.