If you already have a dog and are planning on getting another, introduce them by immediately walking them together the 1st time they meet. The distraction of the walk keeps them from getting possibly hostile and gives them time relax and adjust to another dog during a fun activity for them
Also, have them meet on neutral territory, not in the house!
if you believe that, you miss a few decades of history in your knowledge ..
but then what's the point of arguing ? :)