Pathways of Light

  • V. Srinivasa ChakravarthyEmail author


This chapter is about the problem of vision, which has, interestingly, two subproblems. One of these subproblems is an easy one, the other hard. The easy problem of vision concerns itself with what happens to light when it enters the brain through the portals called eyes. What is its path? What are the major stopovers? What exactly happens at each of these stopovers? The problem is not easy because it is known in all its immense detail. In fact, the details of the visual system are not completely unraveled, despite the intense and sometimes disproportionate attention paid to vision by the neuroscience community. It is easy because the problem is mainly one of getting all the relevant details by expending adequate resources, human and otherwise, and a lot of time. It is easy in the sense that there is a method to go about it. The other problem of vision is not so easy because there is no well-defined method that allows you to make predictable progress in that area. The hard problem of vision deals with the more interesting, popular question: how do we see? What are the exact neural events that conspire to enable us to have the moment-to-moment revelation of a moving, multicolored vision of the universe? It is not that neuroscience failed to make any progress in this matter. It is just that this second problem resides on the borders of science and philosophy, leading us on into deeper questions regarding the nature of consciousness and so on. The standard evidence-based methods of science seem to flounder and buckle in tacking the second problem.


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© Springer Nature Singapore Pte Ltd. 2019

Authors and Affiliations

  1. 1.Indian Institute of Technology MadrasChennaiIndia

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