Section 2 : First-order logic: Syntax and semantics

Commentary

Section Goals

• To discuss syntax, semantics, and the use of first-order logic.
• To introduce and exemplify the knowledge engineering process.

Section Notes

• Parts of this section may be skipped by those who have studied first-order inference in an undergraduate AI course. However, even for those students, further study of the in-depth issues in this section is encouraged to pave the way for the future sections and units.

Learning Objectives

Learning Objective 1

• Describe the syntax and semantics of first-order logic.
• Explain the following concepts or terms:
  • First-order logic
  • Higher-order logic
  • Temporal logic
  • Domain
  • Interpretation
  • Predicate symbols
  • Quantifiers
• Apply first-order logic to represent knowledge in several cases, such as the kinship domain, numbers, sets, and the wumpus world.
• Discuss the general knowledge engineering process based on first-order logic.

Objective Readings

Required readings:

Reading topics:

First-Order Logic (see Chapter 8 of AIMA3ed).

Objective Questions

• What "common mistakes" are discussed in the text when using universal and existential quantification to express sentences? Explain why these mistakes occur.

Objective Activities

• Complete Exercise 8.24 of AIMA3ed.