Criteria for Symbol Grounding

1
Criteria for Symbol Grounding

• Lee McCauley

2
Definitions

• Grounding a representation is grounded when the
  agent can reason about all of the perceivable
  features of the entity represented and can
  construct an instantiation of the category
• can reason does not mean will reason
• an instantiation of a category does not mean
  recreating a particular episode

3
Definitions (cont.)

• Meaning a grounded representations
  associations with other grounded representations
• associations include all possible relationships
• Logical (isa, hasa, etc.)
• Temporal
• Spatial
• Implicit

4
What properties are necessary for symbol
grounding?

• Primitives
• Iconic Representations/Perceptual Symbols
• Structural Coupling
• Systemic Learning

5
Primitives

• The agent must have some primitive semantic
  elements
• Perceptual primitives
• Primitive motivators
• Primitive actions

6
Iconic/Perceptual Symbols

• Every representation in the system needs to be an
  icon of the features that feed into it
• This is very much (although not exactly) like
  Barsalous perceptual symbols
• No matter what depth the representation might be
  at, it resembles the salient features that
  comprise it
• There are no truly arbitrary symbols

7
Structural Coupling/Synchronization

• The agent is embodied within its environment
• The agent can change the environment through its
  actions in such a way that the environments
  impact on the agent is modified

8
Systemic Learning

• Systemic learning means that the structure of the
  representations change, not just the contents
• Examples
• Neural networks
• Some symbolic systems (would be possible in Lisp)
• For any complex enough agent in a complex enough
  environment to be interesting, the iconic
  representations and embodiment require a systemic
  learning mechanism

9
Motivational adaptation (a form of Systemic
Learning)

• Any sufficiently complex environment/agent
  interaction has intermediate goals that are not
  expressed by the primitive motivators
• A grounded agent should be able to modify its
  motivational structure in a way that increases
  its ability to satisfy its primitive motivators

10
Properties Whats missing or shouldnt be
present?

• Primitives
• Iconic Representations/Perceptual Symbols
• Structural Coupling
• Systemic Learning
• ??

11
Quotes

• "It is possible to store the mind with a million
  facts and still be entirely uneducated."-- Alec
  Bourne
• "Knowledge must be gained by ourselves. Mankind
  may supply us with the facts but the results,
  even if they agree with previous ones, must be
  the work of our mind."-- Benjamin "Dizzy"
  Disraeli (1804-81), First Earl of Beaconsfield
  British politician

12
Quotes (cont.)

• Computers are useless. They can only give you
  answers. -- Pablo Picasso (1881 - 1973)
• "The best computer is a man, and it's the only
  one that can be mass-produced by unskilled
  labor."-- Wernher Magnus Maximilian von Braun
  (1912-77), German-born American rocket engineer

13
Quotes (cont.)

• "The factory of the future will have two
  employees a man and a dog. The man's job will be
  to feed the dog. The dog's job will be to prevent
  the man from touching any of the automated
  equipment."-- Warren G. Bennis (b. 1925),
  American writer, educator, University of Southern
  California sociologist

14
(No Transcript)