An interesting question came up recently about Zendo. It says in the rule book that a Rule cannot refer to anything outside the Koan in space or time. Clearly, Koans can refer to colour, which is an inherent property of the pieces. However, a Rule that was suggested was A Koan has the buddha nature, if and only if it contains a stack whose total pip value is the same as the number of letters in the colour of the top-most pyramid in that stack. Now, I would argue that that's NOT allowed by the rule, as it's language dependent, and thus refers to something outside of the Koan - i.e. language. "Red" is an inherent property. "R-E-D" is not, for it would be different for French players: "R-O-U-G-E". Am I right in making such a call? Secondly, at ChiTag, Rabbits were giving their Rules a difficulty rating of 1-10. Is there a sanctioned list of example rules that has official ratings, so that a) I can rate rules I invent better and b) I can better invent rules for a particular rating? Timothy