Cognitive Interpretation of Visual Signals

Abstract

How we see, and how we know what we see, are conundrums that have perplexed scientists for decades and intrigued philosophers for centuries. In pre-Socratic times, philosophers attempted to separate interactions with the external world into those that involve the human senses and those that do not involve the senses directly. The theory of Empedocles, typical of the reasoning employed by several early philosophers, suggested that the senses are affected by tiny, particle-like effluences emitted by objects. As the effluences strike the body, they lodge in one set of pores or another depending on their exact size and configuration. Each set of pores gives rise to a particular sensation experienced by the observer. For a stone to be seen as a gray, round object, its effluences would have to be captured by the pores that characterize gray, round objects. These pores are located in the eyes, because the object is seen. Objects that are heard emit effluences that are captured by the ears, and effluences that are captured by the nose give rise to the sensation of smell.