CLDs use only variables and causal links. Each noode must be a Variable. [⇒ Attribution (Zurechnung) ⇒ Event (Ereignis)]
**A word on creating variables.**
All "variable" means is that it is a changeable thing.
It does not have to be precisely quantifiable. In fact some of the most critical variables have no precise measurements but people can report on changes without numeric measurements.
For example: More or less trust. More or less fear.
Don't shy away from these "fuzzy" variables or "hidden" variables. They are often the leverage points in social systems. They often yield critical insights into the behavior of the system you are observing or experiencing.