Intellectual Property and the Kindergarten

After many quarrels about who determines the rules of their games (including who is the princess and who is the horse), my children have reported that they have now finally found a new rule making their Kindergarten life more peaceful: The one who has invented the game determines the rules. This made me think.

After a first attack of fatherly pride, I am now wondering whether this new rule really decreases the number of arguments or rather provokes new arguments on novelty, inventiveness and inventorship...