/* Learning family relationships  (Quinlan, MLJ 90) */
/* Any of the BK predicates can be learnt using the others */

background([husband/2,
            wife/2,
            father/2,
            mother/2,
            son/2,
            daughter/2,
            brother/2,
            sister/2,
            uncle/2,
            aunt/2,
            nephew/2,
            niece/2]).

propositional([]).

husband(christopher,penelope).
husband(andrew,christine).
husband(arthur,margaret).
husband(james,victoria).
husband(charles,jennifer).

wife(penelope,christopher).
wife(christine,andrew).
wife(margaret,arthur).
wife(victoria,james).
wife(jennifer,charles).

mother(penelope,arthur).
mother(penelope,victoria).
mother(christine,james).
mother(christine,jennifer).
mother(victoria,colin).
mother(victoria,charlotte).

father(christopher,arthur).
father(christopher,victoria).
father(andrew,james).
father(andrew,jennifer).
father(james,colin).
father(james,charlotte).

daughter(victoria,christopher).
daughter(victoria,penelope).
daughter(jennifer,andrew).
daughter(jennifer,christine).
daughter(charlotte,james).
daughter(charlotte,victoria).

son(arthur,christopher).
son(arthur,penelope).
son(james,andrew).
son(james,christine).
son(colin,james).
son(colin,victoria).

brother(arthur,victoria).
brother(james,jennifer).
brother(colin,charlotte).

sister(victoria,arthur).
sister(jennifer,james).
sister(charlotte,colin).

uncle(arthur,colin).
uncle(arthur,charlotte).
uncle(charles,colin).
uncle(charles,charlotte).

aunt(margaret,colin).
aunt(margaret,charlotte).
aunt(jennifer,colin).
aunt(jennifer,charlotte).

nephew(colin,margaret).
nephew(colin,arthur).
nephew(colin,jennifer).
nephew(colin,charles).

niece(charlotte,margaret).
niece(charlotte,arthur).
niece(charlotte,jennifer).
niece(charlotte,charles).