# David Marr

David Courtnay Marr (19 January 1945 – 17 November 1980) was a British neuroscientist and psychologist, known for integrating results from psychology, artificial intelligence, and neurophysiology into new models of visual processing.

## Quotes

* To understand the relationship between behavior and brain one has to begin by defining the function, or computational goal, of a complete behavior. Only then can a neuroscientist determine how the brain achieves that goal.
** In: Paul W. Glimcher (2004). Decisions, Uncertainty, and the Brain.

### Representation and recognition of the spatial organization of three-dimensional shapes, 1978

Marr, David, and Herbert Keith Nishihara. "Representation and recognition of the spatial organization of three-dimensional shapes." Proceedings of the Royal Society of London B: Biological Sciences 200.1140 (1978): 269-294.
* Vision is a process that produces from images of the external world a description that is useful to the viewer and not cluttered with irrelevant information.
** as cited in Steven Yantis (2001) Visual Perception: Essential Readings, p. 117.
* A representation is a formal system for making explicit certain entities or types of information, together with a specification of how the system does this. And I shall call the result of using a representation to describe a given entity a description of the entity in that representation.
* The critical act in formulating computational theories turns out to be the discovery of valid constraints on the way the world is structured -- constraints that provide sufficient information to allow the processing to succeed.
* The primitives of a representation are the most elementary units of shape information available in a representation.
** p. 274

### Vision, 1982

* Vision is the process of discovering from images what is present in the world, and where it is.
** p. 3, cited in: M. R. Bennett, ‎P. M. S. Hacker (2012). History of Cognitive Neuroscience.
* The abstract properties of this mapping are defined precisely, and its appropriateness and adequacy for the task at hand are demonstrated.
** p, 24
* In order to understand bird flight, we have to understand aerodynamics; only then does the structure of feathers and the different shapes of bird's wings make sense.
** p. 27
* Vision is a process that produces from images of the external world a description that is useful to the viewer and not cluttered with irrelevant information.
** p. 31
* [If] we can experimentally isolate a process and show that it can still work well, then it cannot require complex interaction with other parts of vision and can therefore be understood relatively well on its own.

## Quotes about David Marr

* When David Marr at MIT moved into computer vision, he generated a lot of excitement, but he hit up against the problem of knowledge representation; he had no good representations for knowledge in his vision systems.
** Marvin Minsky in: David G. Stork (1998). HAL's Legacy: 2001's Computer As Dream and Reality. p. 16
* I am not sure that Marr would agree, but I am tempted to add learning as the very top level of understanding, above the computational level. [...] Only then may we be able to build intelligent machines that could learn to see—and think—without the need to be programmed to do it.
** Tomaso Poggio, Vision, 2010, The MIT Press; Afterword, P.367