To get the answer we seek, we must add one more rule for this answer only:
F. The employee is not insured.
not-5
We now have a total of 4 + 2 + 4 + 2 + 2 + 1 occurrences of statements, or 15 occurrences. This is beyond the capacity of the existing machine. But fortunately Rule F and Rule A cancel each other; they may both be omitted; and this gives us 10 occurrences instead of 15. In other words, all the possible statuses under “Rule B and Rule C and Rule D and Rule E” will give us the answer we seek.
The rephrasing and reasoning we have done here is perhaps not easy. For example, going from the logical pattern
Only igs may be ows
to the logical pattern
If it is an ow, then it is an ig
as we did in rephrasing Rule B, deserves rather more thought and discussion than we can give to the subject here. A person who is responsible for preparing problems for the Logical-Truth Calculator should know the algebra of logic.
Choosing an appropriate grouping, we now set on the machine: