You don't need to evaluate every possible combination.
You need to evaluate each rule one by one and if one of the rules is false you make the decision false.
VB Code:
  1. decision = (rule1 And rule2 And rule3 And rule4)
Or
VB Code:
  1. decision = True
  2. decision = decision And rule1
  3. decision = decision And rule2
  4. decision = decision And rule3
  5. decision = decision And rule4
decision and the rules are booleans.