Unification is an important aspect of resolution. For each of the following attempted unifications, tell what variable instantiations and unifications result.
|
Here is a sorites (plural, soriteses) from Lewis Carroll:
This can be turned into a set of clauses in predicate calculus by
(Note: I'm using => for implies, - for not, and v for or.) So,
Statement |
Implication |
Clause |
---|---|---|
1. All my sons are slim. |
son => slim |
-son v slim |
2. No child of mine is healthy who takes no exercise. |
-exercise => -healthy |
exercise v -healthy |
3. All gluttons, who are children of mine, are fat. |
glutton => -slim |
-glutton v -slim |
4. No daughter of mine takes any exercise. |
-son => -exercise |
son v -exercise |
Resolve the following pairs of clauses:
Clauses to resolve |
Resolution |
---|---|
1. -son v slim |
5. |
1. -son v slim |
6. |
2. exercise v -healthy |
7. |
5. |
8. |
Here, just for fun, is another sorites:
|
Resolve the following pairs of clauses:
Clauses to resolve |
Resolution |
---|---|
1.
-pass(X, history) v -win(X, lottery) v happy(X) |
3. |
3. |
5. |
5. |
7. |
7. |
9. |
6. lucky(john) |
10. |