Studies[x, SocialScience] IF Isa[y, SocialScience] AND Subject[Major[x], y]
Likes[x, ComputerScience] IF Likes[x, Programming] AND Likes[x, Math]
Likes[x, ComputerScience] IF Likes[x, Programming] AND Plays[x, ComputerGames]
Likes[Sally, Math]
Likes[Steve, Math]
Likes[Mary, Programming]
Likes[Steve, Programming]
Likes[Lisa, Programming]
Plays[Lisa, ComputerGames]
Subject[Major[Tom], History]
Subject[Major[Karen], Polisci]
Isa[History, SocialScience]
Isa[Polisci, SocialScience]