Clarifying Clarifications ~ Universal 'And' to the Rescue
A business rule is always constraining in the sense that if enforced it inevitably shapes behavior. But what about guidance statements that do not constrain in that sense? For example, consider the statement: A person of any age may hold a bank account. What kind of statement is that? Even if not a rule -- it does not constrain -- it clearly does provide some form of guidance.
In BRS RuleSpeak®, such a clarification is called a Permission Statement. The essence of the statement is to indicate that something is allowed -- that is, permitted. It is unconditional in the sense that it does not contain explicit conditions -- that is, no 'only if this' or 'only if that.'
"Unconditional" does not, of course, mean that all relevant rules about holding bank accounts have been suddenly suspended. For example, even though the Permission Statement does not mention any of the following rules explicitly, they presumably still all nonetheless apply.
A person must show acceptable identification when a bank account is opened.
An initial deposit of at least $1 must be made when a bank account is opened.
A person must have an address in the same country as the bank account.
A person under 18 may hold a bank account only if a parent of that person is also a signatory for that bank account.
If desired, these conditions could be brought into the Permission Statement explicitly. In RuleSpeak, this expanded statement would appear as follows:
A person of any age may have a bank account only if all of the following are true:
- The person shows acceptable identification when the bank account is opened.
- An initial deposit of at least $1 is made when the bank account is opened.
- The person has an address in the same country as the bank account.
- A parent of that person is also a signatory for that bank account if the person is under 18.
Given that there might be hundreds or even thousands of such rules about bank accounts, this approach quickly gets out of hand. Imagine replicating all the bank account rules in every Permission Statement worth recording!
Fortunately, there is no need to do so. Rule theory has a fundamental assumption, called the "universal AND" which, as the name suggests, prescribes that all rules must be "anded." This applies to clarifications -- Permission Statements -- as well as to rules. So all we need to do is simply state the clarification itself -- for example, a person of any age may hold a bank account. We rely on the Universal And to silently 'and in' all the rules still applying -- any and all "only if's" relevant to the circumstances.
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