Turner James
Department of Philosophy, University of Sheffield, 45 Victoria Street, Sheffield, S3 7QB UK.
Erkenntnis. 2025;90(5):1695-1720. doi: 10.1007/s10670-023-00773-5. Epub 2024 Jan 22.
There are three main accounts of the proper function of the low mood system (LMS): the social risk theory, the disease theory, and the propitiousness theory. Adjudicating between these accounts has proven difficult, as there is little agreement in the literature about what a theory of the LMS's proper function is supposed to explain. In this article, drawing upon influential work on the evolution of affective systems, such as the disgust system and the fear system, I argue that a theory of the proper function of the low mood system should: (i) account for the reliable, distal causes and effects of the system's activation, and (ii) explain how having a system that performed such a function increased fitness in ancestral environments. On this basis, I show that the proper function of the low mood system is to limit resource expenditure in relatively unpropitious circumstances, exactly as hypothesised by the propitiousness theory.
关于低情绪系统（LMS）的正常功能，主要有三种解释：社会风险理论、疾病理论和吉祥理论。事实证明，在这些解释之间进行裁决很困难，因为文献中对于LMS正常功能的理论应该解释什么几乎没有共识。在本文中，借鉴了诸如厌恶系统和恐惧系统等情感系统进化方面的有影响力的研究，我认为低情绪系统正常功能的理论应该：（i）解释该系统激活的可靠、远端原因和结果，以及（ii）解释拥有这样一个执行该功能的系统如何在祖先环境中提高适应性。在此基础上，我表明低情绪系统的正常功能是在相对不利的情况下限制资源消耗，正如吉祥理论所假设的那样。
