001 package aima.logic.fol.kb;
002
003 import aima.logic.fol.domain.DomainFactory;
004 import aima.logic.fol.domain.FOLDomain;
005 import aima.logic.fol.inference.InferenceProcedure;
006
007 /**
008 * @author Ciaran O'Reilly
009 *
010 */
011 public class FOLKnowledgeBaseFactory {
012
013 public static FOLKnowledgeBase createKingsKnowledgeBase(
014 InferenceProcedure infp) {
015 FOLKnowledgeBase kb = new FOLKnowledgeBase(DomainFactory.kingsDomain(),
016 infp);
017 kb.tell("((King(x) AND Greedy(x)) => Evil(x))");
018 kb.tell("King(John)");
019 kb.tell("King(Richard)");
020 kb.tell("Greedy(John)");
021
022 return kb;
023 }
024
025 public static FOLKnowledgeBase createWeaponsKnowledgeBase(
026 InferenceProcedure infp) {
027 FOLKnowledgeBase kb = new FOLKnowledgeBase(DomainFactory
028 .weaponsDomain(), infp);
029 kb
030 .tell("( (((American(x) AND Weapon(y)) AND Sells(x,y,z)) AND Hostile(z)) => Criminal(x))");
031 kb.tell(" Owns(Nono, M1)");
032 kb.tell(" Missile(M1)");
033 kb.tell("((Missile(x) AND Owns(Nono,x)) => Sells(West,x,Nono))");
034 kb.tell("(Missile(x) => Weapon(x))");
035 kb.tell("(Enemy(x,America) => Hostile(x))");
036 kb.tell("American(West)");
037 kb.tell("Enemy(Nono,America)");
038
039 return kb;
040 }
041
042 public static FOLKnowledgeBase createLovesAnimalKnowledgeBase(
043 InferenceProcedure infp) {
044 FOLKnowledgeBase kb = new FOLKnowledgeBase(DomainFactory
045 .lovesAnimalDomain(), infp);
046
047 kb
048 .tell("FORALL x (FORALL y (Animal(y) => Loves(x, y)) => EXISTS y Loves(y, x))");
049 kb
050 .tell("FORALL x (EXISTS y (Animal(y) AND Kills(x, y)) => FORALL z NOT(Loves(z, x)))");
051 kb.tell("FORALL x (Animal(x) => Loves(Jack, x))");
052 kb.tell("(Kills(Jack, Tuna) OR Kills(Curiosity, Tuna))");
053 kb.tell("Cat(Tuna)");
054 kb.tell("FORALL x (Cat(x) => Animal(x))");
055
056 return kb;
057 }
058
059 public static FOLKnowledgeBase createRingOfThievesKnowledgeBase(
060 InferenceProcedure infp) {
061 FOLKnowledgeBase kb = new FOLKnowledgeBase(DomainFactory
062 .ringOfThievesDomain(), infp);
063
064 // s(x) => ~c(x) One who skis never gets caught
065 kb.tell("(Skis(x) => NOT(Caught(x)))");
066 // c(x) => ~s(x) Those who are caught don't ever ski
067 kb.tell("(Caught(x) => NOT(Skis(x)))");
068 // p(x,y) & c(y) => s(x) Jailbird parents have skiing kids
069 kb.tell("((Parent(x,y) AND Caught(y)) => Skis(x))");
070 // s(x) & f(x,y) => s(y) All friends ski together
071 kb.tell("(Skis(x) AND Friend(x,y) => Skis(y))");
072 // f(x,y) => f(y,x) Friendship is symmetric
073 kb.tell("(Friend(x,y) => Friend(y,x))");
074 // FACTS
075 // 1. { p(Mike,Joe) } Premise
076 kb.tell("Parent(Mike, Joe)");
077 // 2. { p(Janet,Joe) } Premise
078 kb.tell("Parent(Janet,Joe)");
079 // 3. { p(Nancy,Mike) } Premise
080 kb.tell("Parent(Nancy,Mike)");
081 // 4. { p(Ernie,Janet) } Premise
082 kb.tell("Parent(Ernie,Janet)");
083 // 5. { p(Bert,Nancy) } Premise
084 kb.tell("Parent(Bert,Nancy)");
085 // 6. { p(Red,Ernie) } Premise
086 kb.tell("Parent(Red,Ernie)");
087 // 7. { f(Red,Bert) } Premise
088 kb.tell("Friend(Red,Bert)");
089 // 8. { f(Drew,Nancy) } Premise
090 kb.tell("Friend(Drew,Nancy)");
091 // 9. { c(Mike) } Premise
092 kb.tell("Caught(Mike)");
093 // 10. { c(Ernie) } Premise
094 kb.tell("Caught(Ernie)");
095
096 return kb;
097 }
098
099 // Note: see -
100 // http://logic.stanford.edu/classes/cs157/2008/lectures/lecture15.pdf
101 // slide 12 for where this test example was taken from.
102 public static FOLKnowledgeBase createABCEqualityKnowledgeBase(
103 InferenceProcedure infp, boolean includeEqualityAxioms) {
104 FOLDomain domain = new FOLDomain();
105 domain.addConstant("A");
106 domain.addConstant("B");
107 domain.addConstant("C");
108
109 FOLKnowledgeBase kb = new FOLKnowledgeBase(domain, infp);
110
111 kb.tell("B = A");
112 kb.tell("B = C");
113
114 if (includeEqualityAxioms) {
115 // Reflexivity Axiom
116 kb.tell("x = x");
117 // Symmetry Axiom
118 kb.tell("(x = y => y = x)");
119 // Transitivity Axiom
120 kb.tell("((x = y AND y = z) => x = z)");
121 }
122
123 return kb;
124 }
125
126 // Note: see -
127 // http://logic.stanford.edu/classes/cs157/2008/lectures/lecture15.pdf
128 // slide 16,17, and 18 for where this test example was taken from.
129 public static FOLKnowledgeBase createABCDEqualityAndSubstitutionKnowledgeBase(
130 InferenceProcedure infp, boolean includeEqualityAxioms) {
131 FOLDomain domain = new FOLDomain();
132 domain.addConstant("A");
133 domain.addConstant("B");
134 domain.addConstant("C");
135 domain.addConstant("D");
136 domain.addPredicate("P");
137 domain.addFunction("F");
138
139 FOLKnowledgeBase kb = new FOLKnowledgeBase(domain, infp);
140
141 kb.tell("F(A) = B");
142 kb.tell("F(B) = A");
143 kb.tell("C = D");
144 kb.tell("P(A)");
145 kb.tell("P(C)");
146
147 if (includeEqualityAxioms) {
148 // Reflexivity Axiom
149 kb.tell("x = x");
150 // Symmetry Axiom
151 kb.tell("(x = y => y = x)");
152 // Transitivity Axiom
153 kb.tell("((x = y AND y = z) => x = z)");
154 // Function F Substitution Axiom
155 kb.tell("((x = y AND F(y) = z) => F(x) = z)");
156 // Predicate P Substitution Axiom
157 kb.tell("((x = y AND P(y)) => P(x))");
158 }
159
160 return kb;
161 }
162 }