The Two Fundamental Kinds of Business Rules: Where They Come From and Why They Are What They AreThe two fundamental kinds of business rules relevant to business analysis are definitional rule and behavioral rule. These two kinds of rule come from OMG’s SBVR (Semantics of Business Vocabulary and Business Rules) standard. They have very precise meanings based on formal logic. Here’s some background about that – more than business analysts really need to know, but informative nonetheless. At the end of the discussion I give pragmatic definitions. And the answer to the photo quiz. The SBVR definition for rule is deeply embedded in formal logic, which deals with propositions. In modal logic, propositions can claim different modes. For business rules the two relevant modes are alethic and deontic.
- Alethic rules are true ‘by definition’. As such they cannot be violated. They are about how concepts, knowledge or information are defined or structured.
- Deontic rules are rules that can be violated. They are rules about behavior, not concepts, knowledge or information. Deontic rules are really about people, what they must and must not do, even if their activity (and the rules) are automated.
- Alethic implications (rules) are established by ‘claiming’ necessity. Things are necessarily true. A concept is what it is; says what it says. That’s just the way things are.
- Deontic implications (rules) are established by ‘claiming’ obligation. Behavior is ‘obliged’ to follow the rule. But of course, people don’t always follow the rules, so there can be violations. Major difference.
- Definitional rule: rule that is a claim of necessity
- Behavioral rule: business rule that is a claim of obligation
- Definitional rule: a rule that indicates something is necessarily true (or untrue); a rule that is intended as a definitional criterion for concepts, knowledge or information
- Behavioral rule: a business rule that places an obligation (or prohibition) on conduct, action, practice, or procedure; a business rule whose purpose is to shape (govern) day-to-day business activity
Tags: alethic, behavioral rules, behavioral rules vs. definitional rules, definitional rule, deontic, modal logic, operative rule, SBVR, Semantics of Business Vocabulary and Business Rules, structural rule, under business jurisdiction