A symbolic element of psychohistorical analysis must, of necessity, be more complex than normally used in mathematics. Think on the already common levels of abstraction; the number representing a quantity. From there, we get the variable which represents an unknown number. Functions can represent the change in one variable as another changes. Psychohistory requires higher levels than these- namely, the application of many many functions at a time where each is nonstatic, and capable of change, or even further than that. A society which values money more than ethics weights its choices more towards those ends, and its functional sets reflect this. So one symbol must be used to represent a functional unit at the psychohistorical level. Exactly what that is is up for debate.