Question $3$

Logic

Describe how propositional logic is used to represent knowledge.

Briefly describe what is meant by the grounding problem.

What does it mean for a knowledge base $K$ to entail sentence $?$

In first$-$order logic, what is the difference between a function and a predicate?

Page $6$ of $10$

Describe when one would make use of a Skolem constant.

Encode the statement "everything is bitter or sweet" in first$-$order logic.

Alice wishes to encode the English sentence "frogs are green" in first$-$order logic.

She writes this as AAxFrog$(x{)}^{{?}^{?}}$Grecn$(x).$ Explain the fault in her reasoning and

then write down the correct logical sentence.