Crucial stem cell experiments? Stem cells, uncertainty, and single-cell experiments

Abstract

I have previously argued that stem cell experiments cannot demonstrate that a single cell is a stem cell (Fagan 2013a, b). Laplane and others dispute this claim, citing experiments that identify stem cells at the single-cell level. This paper rebuts the counterexample, arguing that the alleged 'crucial stem cell experiments' do not measure self-renewal for a single cell, do not establish a single cell's differentiation potential, and, if interpreted as providing results about single cells, fall into epistemic circularity. I then discuss the source of the dispute, locating it in differences between philosophical and experimental perspectives.