What does it mean to win an argument?  To outwit, out-logic, or out-word your opponent?

I suggest not.  Let them have their say.  Acknowledge their view.  Tell them you’ll have to think about it.

Taking your ego out of the equation lets you look at it from all the angles to pick the correct side afterwards.  Winning isn’t a matter of you versus them.  It’s a matter of the getting to the right answer, whether it was originally yours or theirs.

Winning every argument is easy.  If you’re willing to lose it first.