From “Sheep are animals,” it follows that “The head of a sheep is the
head of an animal.” Demonstrate that this inference is valid by carrying
out the following steps:
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Translate the premise and the conclusion into the language of first-order logic. Use three predicates:
${HeadOf}(h,x)$ (meaning “$h$ is the head of$x$ ”),${Sheep}(x)$ , and${Animal}(x)$ . -
Negate the conclusion, and convert the premise and the negated conclusion into conjunctive normal form.
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Use resolution to show that the conclusion follows from the premise.