Online research in philosophy

In “The Reappearing Act” István Aranyosi postulates a new way of seeing to solve a puzzle posed in “The Disappearing Act;” an object that is exactly shaded can be seen simply by virtue of its contrast with its environment – just like a shadow. This object need not reflect, refract, absorb or block light. To undermine the motive for this heretical innovation, I generalize the puzzle to situations involving inexact shading. Aranyosi cannot extend his solution to these variations because he needs to conserve principles of camouflage. On the bright side, the solution to the puzzle that I propose in my book Seeing Dark Things does extend to these variations.

The Yale shadow puzzle1 purports to involve the ultimate incompatibility of the following plausible looking principles: (1) If X casts any shadow, then some light is falling directly on X. (2) Shadows cannot be cast through an opaque object. (3) Every shadow is the shadow of something. Imagine a high wall casting a shadow on the ground on a sunny day, and a little bird standing on the ground within the shadow cast by the wall. Is the shadow that is present on the ground under the bird –let’s mark it with S- the shadow of the bird, or (part of) the shadow of the wall? It cannot be the bird’s, by proposition (1), as the bird does not block any light. Neither can it be the wall’s, by proposition (2), as the wall cannot cast its shadow through the opaque bird. Yet, by proposition (3), it has to be the shadow of something. Roy Sorensen has offered neat looking solution to the puzzle; however, part of my goal in this paper is to show that this solutions doesn’t work for a new version of the Yale shadow puzzle, which I call “The Bilkent shadow puzzle”, in acknowledgment of my own academic affiliation. The remaining issue will be to offer a new solution that would cover both puzzles. As it will turn out, the solution is based on a peculiar understanding of the ontology of shadows.

I discuss a solution to the Yale shadow puzzle, due to Roy Sorensen, based on the actual process theory of causation, and argue that it does not work in the case of a new version of the puzzle, which I call "the Bilkent shadow puzzle". I offer a picture of the ontology of shadows that constitute the basis for a new solution that uniformly applies to both puzzles.

Berkeley thinks that we only see the size, shape, location, and orientation of objects in virtue of the correlation between sight and touch. Shadows have all of these spatial properties and yet are intangible. In Seeing Dark Things (2008), Roy Sorensen argues that shadows provide a counterexample to Berkeley's theory of vision and, consequently, to his idealism. This paper shows that Berkeley can accept both that shadows are intangible and that they have spatial properties.

Despite its admirable bottom-up methodology, Roy Sorensen's Seeing Dark Things (OUP, 2008) raises difficult theoretical questions concerning the metaphysics and perception of absences. Metaphysical difficulties include how to individuate, count, locate, and classify absences, and what determines their features. Perceptual difficulties include how to distinguish experiences of absences and presences, especially when nonveridical, and what subjects contribute to perceptual experience according to Sorensen's causal theory. In addition to articulating these difficulties, this paper also presents and explores, on Sorensen's terms, an alternative account of silence.

Despite its admirable bottom-up methodology, Roy Sorensen's Seeing Dark Things (OUP, 2008) raises difficult theoretical questions concerning the metaphysics and perception of absences. Metaphysical difficulties include how to individuate, count, locate, and classify absences, and what determines their features. Perceptual difficulties include how to distinguish experiences of absences and presences, especially when nonveridical, and what subjects contribute to perceptual experience according to Sorensen's causal theory. In addition to articulating these difficulties, this paper also presents and explores, on Sorensen's terms, an alternative account of silence.

In his latest book, Roy Sorensen offers a solution to a puzzle he put forward in an earlier article -The Disappearing Act. The puzzle involves various question about how the causal theory perception is to be applied to the case of seeing shadows. Sorensen argues that the puzzle should be taken as bringing out a new way of seeing shadows. I point out a problem for Sorensen’s solution, and offer and defend an alternative view, according to which the puzzle is to be interpreted as showing a new way of seeing objects, in virtue of their contrast with light.

The eclipse riddle -- Seeing surfaces -- The disappearing act -- Spinning shadows -- Berkeley's shadow -- Para-reflections -- Para-refractions : shadowgrams and the black drop -- Goethe's colored shadows -- Filtows -- Holes in the light -- Black and blue -- Seeing in black and white -- We see in the dark -- Hearing silence.