Unless your argument is about who has better insults
If a person is using pointless insults it means that person has lost the argument and can't admit it or say anything. If it started out that way that person fails at life.
And using my dashing good looks and charm helps me win with your mother.
Your argument is invalid because your mother has promiscious sex with numerous strangers. Snap!
I'd say ignore insults although, and other personal things (try to avoid using yourself as an example for anything) and just focus on the points of the argument. When one person is using insult like "Did your mother drop you on the head or something?" or "If you actually went to school, you'd know that" and the other person is actually arguing about the issue and ignoring those distractions, it's clear who has the upperhand, regardless of topic.
I wish I could favorite this post one hundred times.