Experiencing failure: the twofold cause of error in Stoicism

According to Stoicism, nature has endowed us with reason, enabling us, through the function of kataleptic impressions, to perceive the world truly. Yet most people deviate from this ideal. To explain this, the Stoics identify two causes: (a) the persuasiveness of impressions and (b) the teachings of our associates. While both Galen and Posidonius challenge the validity of these causes, and many scholars highlight their complexity, this paper aims to provide a deeper Stoic foundation for them. As I will propose, addressing these two causes requires a comprehensive analysis of several aspects of Stoic ontology, epistemology, and causation. This paper argues that the persuasiveness of impressions is rooted, on the one hand, in the intricate causal structure of the Stoic world and the similarities between the causal interactions our soul establishes with virtue and preferable externals, and, on the other hand, in the resemblance between the affections experienced in both passions and virtuous emotions—specifically, the experience of expansion and contraction of the soul when we gain or are deprived of something. Furthermore, I will contend that the influence of associates affects our evaluative judgments due to the causal power of beliefs, which is continually reinforced by the persuasiveness of relevant impressions. To support these conclusions, a detailed examination of both the Stoic theory of causation and the status of sayables in Stoic ontology is essential.