 The direct observational status of the familiar global spacetime symmetries leads us to an epistemological aspect of symmetries. According to Wigner, the spatiotemporal invariance principles play the role of a prerequisite for the very possibility of discovering the laws of nature: “if the correlations between events changed from day to day, and would be different for different points of space, it would be impossible to discover them” (Wigner, 1967, p. 29). For Wigner, this conception of symmetry principles is essentially related to our ignorance (if we could directly know all the laws of nature, we would not need to use symmetry principles in our search for them). Others, on the contrary, have arrived at a view according to which symmetry principles function as “transcendental principles” in the Kantian sense (see for instance Mainzer, 1996). It should be noted in this regard that Wigner’s starting point, as quoted above, does not imply exact symmetries — all that is needed epistemologically is that the global symmetries hold approximately, for suitable spatiotemporal regions, such that there is sufficient stability and regularity in the events for the laws of nature to be discovered.