First thing you have to do is unearth them, the differences. If you have no success in doing this, the second thing you have to do is call the second thing the first thing and make up a difference, just to get the ball rolling. Consider it a little white lie for the common good.
If the individual you’re trying to settle differences with objects to your calling the second thing the first thing, say, “Well there you go. There’s a difference needs settling. Let’s take a bite out of something real, something substantial, like the way you get hung up on technicalities. How can you expect me to accept that kind of avoidance tactic?”
Nine times out of ten a statement like this will trigger dismay and in extreme cases stupefaction; or the opposite, indignation and anger. Depending on which way they go, you can now determine what approach to take.
Stay calm. Remember that you are dealing with a sick person. You may even be dealing with something much deeper than differences. You may be dealing with a recalcitrant.
At this point get your defenses up and be ready to strike out.