  We make moral errors, therefore, by failing to calculate pleasures and pains correctly in making moral choices, which happens when we do not keep in mind ‘the most important things’ (ta kuriôtata) or rules of Epicureanism. Philodemus thinks it important not only to understand, but also to memorize the cardinal tenets, which help us to measure our choices and avoidances by the naturally given ends, not merely—as some Epicureans held—because knowing the cardinal tenets lends tranquillity of mind ([On Choices and Avoidances] XI 7–20). He also argues, in Pros tous […], that easily memorized, abbreviated formulations of the cardinal maxims are useful, and he gives us (IV 9–14) the pithiest formulation of Epicurean tenets, the ‘Fourfold Drug’ (tetrapharmakos logos): ‘god is not fearsome, death not frightening, the good easily got, the bad easily endured’. The reader is advised constantly to bear in mind these four tenets, which are grounded by Philodemus in various places, including in [On Choices and Avoidances], where they are called simply ‘The Four’.