WorksheetsQuiz on Inference in First Order Logic
Total questions: 20
Worksheet time: 10mins
What is the main purpose of inference in First Order Logic (FOL)?
To create random statements
To memorize facts
To derive new facts from known ones
To eliminate all known facts
Which quantifiers are used in First Order Logic?
¬ and ⊕
∀ and ∃
∧ and ∨
→ and ↔
What does Universal Instantiation (UI) allow you to do?
Create a new constant
Negate a statement
Generalize a specific instance to all cases
Apply a general statement to a specific instance
What is an example of Existential Generalization (EG)?
If Priyanka got good marks, then someone got good marks
If all students wear uniforms, then John wears a uniform
If all bulbs are 60W, then one bulb is 60W
If John likes ice cream, then everyone likes ice cream
What is a key problem with propositionalization in FOL?
It can generate too many irrelevant sentences
It requires more constants
It eliminates all facts
It simplifies the logic too much
What is the core function of an inference engine?
To create random facts
To apply logic to derive new facts
To eliminate contradictions
To memorize all known facts
Which of the following describes a Horn Clause?
A conjunction of all literals
A statement with only negative literals
A statement with no literals
Disjunction of literals with ≤1 positive literal
What is the first step in the resolution process?
Convert statements to First-Order Logic
Convert to propositional logic
Negate the goal statement
Apply the resolution rule
What does Backward Chaining do in an inference engine?
Starts with known facts and works forward
Generates random facts
Starts with the goal and works backward
Eliminates all irrelevant facts
What is the result of applying resolution to prove a statement?
It eliminates all known facts
It generates new facts
A contradiction proves the statement is false
A contradiction proves the statement is true
What is the purpose of Universal Generalization (UG)?
To apply a general statement to a specific instance
To generalize from specific instances to all cases
To negate a statement
To create a new constant
In First Order Logic, what does the symbol ∃ represent?
Disjunction
Conjunction
Universal quantifier
Existential quantifier
What is a characteristic of First Order Logic compared to Propositional Logic?
It is simpler and requires no conversion
It does not allow for inference
It only works with ground facts
It is more expressive and uses quantifiers
Which of the following best describes Forward Chaining?
Goal-driven reasoning
Starts from goal and works backwards
Data-driven reasoning
Uses depth-first search
In Backward Chaining, which of the following is true?
It applies rules from known facts to reach a conclusion
It begins with a goal and works backward to verify known facts
It always uses breadth-first search
It is not used in expert systems
What type of clause is this: ¬p ∨ ¬q ∨ r?
Definite Clause
Conjunctive Clause
Horn Clause
Atomic Clause
Which of the following is an example of a definite clause?
¬P ∨ Q ∨ R
King(x) ∧ Greedy(x) ⇒ Evil(x)
P ∨ Q
¬King(x) ∨ Evil(x)
What is the final goal of applying the resolution method?
To match a goal to sub-goals
To convert into first-order clauses
To identify all known facts in the system
To reach a contradiction and prove the theorem
In the resolution method, what is the form of knowledge base required?
Disjunctive Normal Form (DNF)
First-order normal form
Horn clause form
Conjunctive Normal Form (CNF)
In the resolution method, what is the result of resolving the following two clauses?
Clause 1: ¬Animal(x) ∨ Eats(John, x)
Clause 2: Animal(Apple)
Eats(John, Apple)
¬Eats(John, Apple)
Animal(Apple) ∨ Eats(John, x)
No resolution possible
