Theoretical Review

Psychonomic Bulletin & Review

, Volume 20, Issue 5, pp 905-915

First online:

We infer light in space

  • James A. SchirilloAffiliated withDepartment of Psychology, Wake Forest University Email author 


In studies of lightness and color constancy, the terms lightness and brightness refer to the qualia corresponding to perceived surface reflectance and perceived luminance, respectively. However, what has rarely been considered is the fact that the volume of space containing surfaces appears neither empty, void, nor black, but filled with light. Helmholtz (1866/1962) came closest to describing this phenomenon when discussing inferred illumination, but previous theoretical treatments have fallen short by restricting their considerations to the surfaces of objects. The present work is among the first to explore how we infer the light present in empty space. It concludes with several research examples supporting the theory that humans can infer the differential levels and chromaticities of illumination in three-dimensional space.


Brightness Color constancy Illumination Lightness Inferred illumination Space perception