Kripke (1981) famously posited that pain is identified by its ‘immediate phenomenological quality’, which is contingently connected to the firing of C-fibers. Over the past few decades, these assumptions have been scrutinized and challenged by various scholars, fueled by advances in linguistics, philosophy of mind, and empirical research. In general, pain has thereby moved more and more into the foreground of philosophical discourse. Still, substantial disagreement persists regarding the exact nature of pain, largely due to its seemingly paradoxical and enigmatic characteristics.

My analysis begins with the assumption that broadly construed pain episodes consist of at least four key components: (a) physiological disturbance, (b) phenomenal experience (sensory and affective), (c) action tendencies, and (d) alterations in a broader mental network. Using this framework, we can explore two prominent strands in the current philosophical debate on pain, structured around the ‘problem of parts’ and the ‘problem of plenty’.

The ‘problem of parts’ concerns the challenge of determining which components provide the necessary and sufficient conditions for a pain episode. It requires deciding which components are essential to pain itself, beyond being merely paradigmatic of pain episodes. This discussion leads us to the field of pain linguistics, which examines the seemingly paradoxical folk concept of pain. Furthermore, this discussion involves a closer examination of the phenomenal characteristics of pain episodes, dissociative cases where some experiential components are apparently absent, and the question of whether a unique ‘pain quality’ exists that is common to all pains.

The ‘problem of plenty’ addresses how the relevant components of a pain episode relate to each other. For example, it questions how closely the experiential component is tied to the presence of a particular physiological disturbance or the elicitation of a specific action. This debate relates to the motivation of strong intentionalist theories, which focus on what pains are ‘about’. Here, I will focus on proponents of indicative and imperative variants while considering the causal covariance and biological function of pain. Additionally, I will reflect on the broader issue of how to naturalize pain in light of its complexity and heterogeneity, including insights from current developments in neuroscience.

Finally, I will argue for the future development of a research program focused on the challenges posed by chronic pain. This focus could foster stronger interdisciplinary connections to clinical research and practice, and advance discussions on topics that have received insufficient attention in pain philosophy so far. Emphasizing chronic pain opens new lines of research concerning, for example, the phenomenology of pain experiences and their dynamic generation and maintenance.