Right -- that's why I am using `is_Integer`. If the m is Mod() then it was unevaluated and not an Integer so I can't conclude anything. If the assumption system is smart it will tell me that Mod(integer, 4) is an integer but I don't know the value so I shouldn't conclude. Another way of saying this is `if m in [1, 2, 3]:` -- maybe that would be better?