This section is concerned with two very powerful elements of the proofmaking arsenal: “Parity” is a way of referring to the result of an even/odd calculation; Counting arguments most often take the fo...This section is concerned with two very powerful elements of the proofmaking arsenal: “Parity” is a way of referring to the result of an even/odd calculation; Counting arguments most often take the form of counting some collection in two different ways – and then comparing those results. These techniques have little to do with one another, but when they are applicable they tend to produce really elegant little arguments.