Shadows appear to be counterexamples to the causal theory of perception. After all, an absence of light cannot reflect light into our eyes. Roy Sorensen sets out to resolve this anomaly and to show how the causal theory solves a broad range of visual puzzles about dark things.

Roy Sorensen here defends the causal theory of perception by treating absences as causes. He draws heavily on common sense and psychology to vindicate the assumption that we directly perceive absences.

'OH! The Things You Can See In The Dark!' is a picture book for ages 3 and up. The premise of the book is to reveal that which can only be seen in the dark or those things made more glorious in the absence of light. While we may often perceive the dark to be ominous, the book shows a magical aspect of the night through the vibrant and lush imagery used. There may be a note of tension in a storm cloud or a rolling sea, but the components of the images are familiar and the scene is ultimately quieting, curious and inviting. Showing the dark as a place of discovery offers an opportunity to engage in the wonder and beauty of the night.