When to use multiple inheritance vs inheritance and method overriding?

I'm developing a Python framework that's used to compose logic formulas. For example, if I request mutual exclusion between a and b, the output would be the Boolean formula:

"(a --> ¬b)^(b --> ¬a)"

In addition, I want to use some formulas as building blocks for building different types of formulas, such as formulas in Linear Temporal Logic (which is a superset of Boolean logic).

The question is twofold:

1. Do I define one base class (e.g. BooleanFormula) and then:
   • add methods for generating specific formulas (e.g. gen_mutex_formula(a, b)) ?
   • or define more classes (e.g. MutExFormula) that inherit from the fundamental class (BooleanFormula in my example) and generate the formulas in their constructors?

2. When I want to create the new types of formulas, do I inherit from the classes in (1) and mask/override their methods or do I use multiple inheritance. Example of the latter:

   class LTLMutExFormula(LTLFormula, MutExFormula)

What are the criteria and heuristics I should be considering as I'm designing the framework?

PS. Here's what I've been doing so far: link to module on Github