In
artificial intelligence
Artificial intelligence (AI) is intelligence—perceiving, synthesizing, and inferring information—demonstrated by machines, as opposed to intelligence displayed by animals and humans. Example tasks in which this is done include speech r ...
, knowledge-based agents draw on a pool of logical sentences to infer conclusions about the
world
In its most general sense, the term "world" refers to the totality of entities, to the whole of reality or to everything that is. The nature of the world has been conceptualized differently in different fields. Some conceptions see the worl ...
. At the knowledge level, we only need to specify what the agent knows and what its goals are; a logical abstraction separate from details of implementation.
This notion of knowledge level was first introduced by
Allen Newell
Allen Newell (March 19, 1927 – July 19, 1992) was a researcher in computer science and cognitive psychology at the RAND Corporation and at Carnegie Mellon University’s School of Computer Science, Tepper School of Business, and Departmen ...
in the 1980s, to have a way to rationalize an agent's behavior. The agent takes actions based on knowledge it possesses, in an attempt to reach specific goals. It chooses actions according to the
principle of rationality
The principle of rationality (or rationality principle) was coined by Karl R. Popper in his Harvard Lecture of 1963, and published in his book ''Myth of Framework''. It is related to what he called the 'logic of the situation' in an ''Economica'' a ...
.
Beneath the knowledge level resides the
symbol level. Whereas the knowledge level is ''world'' oriented, namely that it concerns the environment in which the agent operates, the symbol level is ''system'' oriented, in that it includes the mechanisms the agent has available to operate. The knowledge level ''rationalizes'' the agent's behavior, while the symbol level ''mechanizes'' the agent's behavior.
For example, in a computer program, the knowledge level consists of the information contained in its data structures that it uses to perform certain actions. The symbol level consists of the program's algorithms, the data structures themselves, and so on.
See also
*
Knowledge level modeling Knowledge level modeling is the process of theorizing over observations about a world and, to some extent, explaining the behavior of an agent as it interacts with its environment.
Crucial to the understanding of knowledge level modeling are Allen ...
*
knowledge relativity
Factual relativism (also called epistemic relativism, epistemological relativism, alethic relativism or cognitive relativism) argues that truth itself is relative. This form of relativism has its own particular problem, regardless of whether one i ...
References
*T. Menzies. Applications of Abduction: Knowledge-Level Modeling. November 1996.
*A. Newell. The Knowledge Level. Artificial Intelligence, 18(1):87-127, 1982.
Artificial intelligence