Practice Exercise 5.A
Logic Syntax

## 2: Learning Goals

• Verify whether a logical statement belongs to the language of propositional definite clauses.
• Verify whether an interpretation is a model of a PDCL KB.
• Model a relatively simple domain with PDCL.

## 3: Directed Questions

In propositional definite clause logic (PDCL),
1. What is an atom? Give the definition and an example from a domain of your choice. [solution]

2. What is a body? Give the definition and an example from a domain of your choice. [solution]

3. What is a definite clause? Give the definition and an example from a domain of your choice. [solution]

4. What is a knowledge base? Give the definition and an example with four clauses from a domain of your choice. [solution]

5. What is an interpretation of a knowledge base KB? Give the definition and an example for your KB. [solution]

6. What is a model of a knowledge base KB? Give the definition and an example for your KB. [solution]

## 4: Exercise: Syntax

Which of the following rules are syntactically invalid in propositional definitive clause logic, and why?
1. bikeCrashed ← cycledDrunk [solution]

2. goByBus ∨ goByCar ← bikeBroke [solution]

3. goByBus ← ¬haveGas ∨ bikeBroke [solution]

## 5: Learning Goals Revisited

• Verify whether a logical statement belongs to the language of propositional definite clauses.
• Verify whether an interpretation is a model of a PDCL KB.
• Model a relatively simple domain with PDCL.