Passage Summary: You shouldn't need a license for a job unless being bad at it could actually hurt someone.

Reasoning: The principle establishes that a licensing requirement is only justified if incompetence in that specific job poses a threat to human health or safety.

Analysis: This principle sets a high bar for government regulation: no safety threat, no license. To justify an argument using this principle, we need a scenario that follows this logic—either concluding that a job *should* be licensed because it is dangerous, or that it *should not* be licensed because it is harmless. The most common application in these questions is the 'contrapositive' approach: showing that because a job is safe, a licensing requirement is inappropriate. Look for an answer that matches this 'if-then' structure regarding safety and regulation.