The basic datatypes of  are written obeying the following methodological guidelines. We formulate them explicitly for several reasons:
If we had pointed out in the guidelines themselves that they are rules of thumb, we would have had to stress phrasings like "if possible", "if adequate", "whenever possible" too much. Thus we formulate them as general statements. Examples from the basic datatypes illustrate their use. The discussion of a guideline justifies the underlying design decision and - as there is no rule without a meaningful exception - shows its limitations.
At certain points, e.g. the naming scheme of axioms, this note differs from the current version 0.7 of the Basic Datatypes. The next revision of the Basic Datatypes will take care of all guidelines presented in this note.
We propose two new annotations in this note: %mono and %implied . Their purpose is explained on pages X and X, respectively. We freely use them throughout the note.