A cyclical Phase or an evolutionary Phase

Modern Finance Assumes Stationary. as well as economics. It assumes that the probability doesn't Change. But the problem is that the process is random rather than deterministic. Stationary assumes that the way you go from summer to winter and back again is always the same. All modern finance assumes stationary. But financae is all about structual changes and how we interpret them. We don't live in a world that is stationary.