Book contents
- Frontmatter
- Contents
- Preface
- I Agents in the World: What Are Agents and How Can They Be Built?
- II Representing and Reasoning
- 3 States and Searching
- 4 Features and Constraints
- 5 Propositions and Inference
- 6 Reasoning Under Uncertainty
- III Learning and Planning
- IV Reasoning About Individuals and Relations
- V The Big Picture
- A Mathematical Preliminaries and Notation
- Bibliography
- Index
3 - States and Searching
from II - Representing and Reasoning
- Frontmatter
- Contents
- Preface
- I Agents in the World: What Are Agents and How Can They Be Built?
- II Representing and Reasoning
- 3 States and Searching
- 4 Features and Constraints
- 5 Propositions and Inference
- 6 Reasoning Under Uncertainty
- III Learning and Planning
- IV Reasoning About Individuals and Relations
- V The Big Picture
- A Mathematical Preliminaries and Notation
- Bibliography
- Index
Summary
Have you ever watched a crab on the shore crawling backward in search of the Atlantic Ocean, and missing? That's the way the mind of man operates.
–H. L. Mencken (1880–1956)The previous chapter discussed how an agent perceives and acts, but not how its goals affect its actions. An agent could be programmed to act in the world to achieve a fixed set of goals, but then it may not adapt to changing goals and so would not be intelligent. Alternatively, an agent could reason about its abilities and its goals to determine what to do. This chapter shows how the problem of an agent deciding what to do can be cast as the problem of searching to find a path in a graph, and it presents a number of ways that such problems can be solved on a computer. As Mencken suggests in the quote above, the mind uses search to solve problems, although not always successfully.
Problem Solving as Search
In the simplest case of an agent reasoning about what it should do, the agent has a state-based model of the world, with no uncertainty and with goals to achieve. This is either a flat (non-hierarchical) representation or a single level of a hierarchy. The agent can determine how to achieve its goals by searching in its representation of the world state space for a way to get from its current state to a goal state.
- Type
- Chapter
- Information
- Artificial IntelligenceFoundations of Computational Agents, pp. 71 - 110Publisher: Cambridge University PressPrint publication year: 2010