We distinguish between first- and second order change and identify the former with perpetual alternation on an existential plane, the second with moving out into existential space. The first type can be demonstrated by two antagonistic processes inherent in a Markov chain of two pairs of complementary values: the chain gradually alternates between the opposite terminal states and the pattern is symmetrical. Such an existential plane catches an essential feature of Heraclitus’ philosophy, and can be illustrated by examples from classical Greek mythology. The same material also exemplifies Lévi-Strauss’ formula of myth, symmetrical in its weak and asymmetrical in 2 its canonical form. Since the weak form equals the orbit of a Klein group, we hypothesize that the canonical form, and thereby symmetry breaking, can be generated by element exchange between two respective Klein groups. The framework for such processes is text variation in folklore, described by ethnosemiotics.