It would be a mistake to believe that the different attempts listed above, somehow form a complete catalogue that allows to classify all possible approaches. In this paragraph such an exotic example, viz. the combinatorial hierarchy, is briefly presented. In this approach the focus is not on the equations of physics themselves, but on the physical constants occurring in them, such as the velocity of light \(c\), the Planck constant \(h\), the mass of the electron \(m_{e}\), and so on. As these values are necessarily finite, it seems worthwhile to investigate whether a finitist approach can explain why these constants have the values they happen to have.  Such approaches are sometimes referred to as “number games”.