From Horses are animals, it follows that The head of a horse is the head of an animal.. Demonstrate that this inference is valid by carrying out the following steps:

1) Translate the premise and the conclusion into the language of 1st -order logic. Use three predicates: HeadOf(h,x) - meaning h is the head of x. Horse(x) Animal(x)

2) Negate the conclusion, and convert the premise and the negated conclusion into conjunctive normal form (CNF).

3) Use resolution to show that the conclusion follows from the premise. Draw the proof tree of resolution, showing the substitutions; see Figure 9.11-12 in the textbook.