But the first chapter is easy to read, and it contains within it a philosophical statement that has influenced researchers in many areas of cognitive science who study things that are distantly related, at least experimentally, to vision. Among other things, the philosophical statement defines three levels of description in the study of the mind. Here are Marr's labels and tasks that Marr gives to the three levels (from Chapter 1, Figure 1-4):
- Computational theory: What is the goal of the computation, why is it appropriate, and what is the logic of the strategy by which it can be carried out?
- Representation and algorithm: How can this computational theory be implemented? In particular, what is the representation for the input and output, and what is the algorithm for the transformation?
- Hardware implementation: How can the representation and algorithm be realized physically?
Marr does such a good job of clearly describing the importance of this approach, and the approach itself has been so influential in cognitive science, that I think anyone who is interested in the discipline should read this first chapter. Thanks to brainsci001, whose real name I do not know, for pointing me to the web copy of the chapter.