```dataview LIST WITHOUT ID file.link WHERE file.cday = date(this.file.name) SORT file.cday ASC ``` Yet first of all, against the radical view, one must note that casters are hardly objects of a perception of physical [[transparency]] involving shadows. In a perception of physical [[transparency]], the background object and the medium object are connected in one and the same perceived scene. Not only, by means of its occupying an intermediate position between the background object and the perceiver, in that scene the medium object filters the light the background object reflects. But also, the background object is a necessary component of that scene, since if the former changed, the latter would change as well. Yet in shadow perception, not only the shadow does not filter the light received by caster - it is a light absorber - but also the caster may not belong to the perceived scene containing the shadow. Hence, if the caster were replaced by another object, notably an object of the same dimensions, the scene with its shadow would not be altered at all.3