One need not even tell a truth to troll - one can merely ask a question that has no good answer.<p>These are my best trolls: &quot;what are the underlying principles that lead you to believe X?&quot; &quot;what evidence - if any - would cause you to hold a different belief?&quot;<p>It&#x27;s the best troll, because when folks come up with no answer they usually resort to ad-hominem attacks. That&#x27;s usually how you know you&#x27;ve raised a very good point.