In praise of Sorensen’s ‘blockage theory’ on shadows

Abstract

In his famous book Seeing Dark Things: The Philosophy of Shadows (2008), Roy Sorensen put forward a ‘blocking theory of shadows’, a causal view on these entities according to which a shadow is an absence of light caused by blockage. This approach allows him to solve a quite famous riddle on shadows, ‘the Yale puzzle’, that was devised by Robert Fogelin in the late 1960s and that Sorensen presents in the form mentioned by Bas van Fraassen (1989). István Aranyosi has recently criticized Sorensen’s solution to the Yale puzzle, on the grounds that it does not resist another version of the riddle, that Aranyosi calls ‘the Bilkent puzzle’. A new perspective on shadows, the ‘Material Exstitution View’, that allegedly permits to solve both puzzles, could be adopted as an alternative. In this paper I will show that Sorensen’s blockage theory can actually handle both the Yale and the Bilkent puzzle, plus another one that I put forward (‘the donut puzzle’), which instead is fatal to Aranyosi’s position. As Sorensen puts it, nothing aside from the original blockage of light is needed. Keywords: Aranyosi, blockage theory, material exstitution view, shadow, Sorensen, Yale puzzle.