VK rules the world. ZK rules the world, too, like a straightedge wielded with eyes closed. Rulers rule in simple ways: by lining things up and by checking they're all in line. Bring your high school math to learn straightedges called SumCheck and SumCalc and begin to appreciate ZK in simple geometric terms. No moon math. We'll visit lines, cubes and polynomials, to see how they can be used to deduce and to generate, to check and to delegate.