 Philosopher Alexander Rosenberg (1997) endorses this version of Wolpert’s theory as vindication of strong molecular reductionism in developmental biology. Manfred Laubichler and Günter Wagner (2001), alongside other biological theorists, reject this version of reductionism (see  Section 10).  Jaeger, Irons, and Monk (2008) propose to reverse Wolpert’s conceptual shift with their “relativistic theory of positional information”, adding a role for regulative feedback by responding cells. Vecchi and Hernández (2014) criticize Wolpert’s and Rosenberg’s reductionist computational embryology as classically preformationist and note explanatory lacunae of the idea of a genetic program pre-established in the egg. This follows Keller (2002), who argues that the twentieth-century consensus on development is essentially preformationist. This brings us to