It may be a matter of common sense based on facts or information from other persons, or various sources, whether religious, historical or scientific, etc. Throughout life we had to ask questions to know something or do certain things. Whether we asked our parents, siblings, relatives, teachers, co-workers, supervisors, boss, police, parking attendant, attorney, or judge? We may even ask God in prayer to answer certain questions for us. Although, we know God probably won't answer us back as in times past, we are left to inquire of others with knowledgeable information or read and study as much as we can and then wait for an answer or clear direction. If there is no definite right or wrong, black and white answers, only gray, then the rule of law may end up being guided by our conscience.