CEFISES Seminar: Wen Shichao, « Bell Curves: Reconciling the Dichotomy Between Typological and Population Thinking »

Livestream  https://youtube.com/live/m764IlIE3Oc

Series: WIP

Speaker: Wen Shichao (UCLouvain)

Title: « Bell Curves: Reconciling the Dichotomy Between Typological and Population Thinking »

Abstract

Building on Sober’s (1980) analysis, this paper proposes that typological and population thinking represent two fundamental ways of interpreting the normal distribution—via the law of errors and the law of variation. Typological thinking emphasizes the average (highlighting common features), while population thinking emphasizes variance (capturing diversity), represented by two statistical models: the ‘wheel of fortune’ and Galton’s quincunx.

These perspectives can be understood as different forms of idealization: one emphasizing constancy and homology by “seeing through variance,” and the other maximizing evolutionary adaptability by randomizing developmental factors. I aim to bridge the gap between them by introducing a framework that breaks the mean into multiple components—gradually dissolving types into a stable yet flexible causal structure. This approach gives rise to a continuum of bell curves, with the mean and variance occupying opposite poles.

I will argue that the middle of this continuum—buffer zones—deserves more attention, as biological entities often exhibit both similarity and variation. Depending on our aims, these zones allow us to shift between different forms of idealization.