“…While it is undisputed that the purpose of QCA is causal inference on the basis of regularity-theoretic relations of necessity and sufficiency (Ragin, 1987, pp. 19–33; Rihoux, 2006, p. 682; Schneider & Wagemann, 2012, p. 8), it has recently been demonstrated that the theory of causality underlying QCA and its associated Boolean-algebraic machinery have not been fully understood, with detrimental consequences for the validity of numerous results presented in applied and methodological research over the last 25 years (Baumgartner, 2015; Baumgartner & Thiem, 2015b, 2015c; Cooper & Glaesser, 2016; Thiem, 2014b, 2014c, 2016a; Thiem & Baumgartner, 2016a, 2016c; Thiem, Baumgartner, et al 2016). It is thus important to first clarify the epistemological underpinnings and the search target of QCA.…”