two kids are liars, three can only say the truth. julia: "jack is only a liar if john is telling the truth." jack: "if joey doesn't lie then, either julia or john do." joey: "jane lies as does julia or jack." john: "if jack is telling the truth, then julia or joey do as well." jane: "if you round up julia,joey and john, you will have at least one liar." the compulsive liars are