I don't bother arguing unless I already know that I'm right.
But that's like saying I don't play chess unless I know I'll win, I don't win until I actually win so, when my victim starts pulling random stuff out of the blue that has nothing to do with what we are talking about or when they start going back on what they've already said is usually when I start wrapping things up.
For instance, I was arguing with someone on the interweb who had just joined the army. He was being disrespectful to some people so I called him out on it and well... I'll just post what he said verbatim:
"Oh and,i love how you think your like a ******* nastradamus, truth is I ****** more girls then you ever seen in your life, and if you ever saw me one and one and tried to insult me i bet you that you would be holding your teeth in your hands, and if I decide to call this a forum... THEN ITS A ****** FORUM YOU LITTLE C0CK ******. (--It wasn't a forum btw---) Telling me to grow up ***** im 19 years old meet me anywhere in chicago and ill show you whose "grown up" stupid ignorant cock sucker. What are you gonna say now? huh you piece of ****? Ill send you a message when I pass osut so u can come over and lick my balls, I pt 4 times a week with the recruits(sometimes im squad leader) I go to ballys 3 times a week(im physically fit and can bench 225) nothing you say to me is important because the truth is your not better then me, and I know it ive earned my promotion to e2 by doing 53 push ups in 2 min, 63 situps in 2 min, and 2 mile run in less then 18... so F.U.C.K YOU SUCK ON MY BALLS!"
All that just because I was trying to convince him that he should be more respectful towards service members who aren't in the infantry.
Anyway after all that I accepted that I was the victor and parted ways with him.