Are we ever in the right? Scientists say, no. When we argue a point, scientists say our reasoning may just be rationalizing.
When we attempt to win our case, no matter how reasoned it may seem, it is invariably biased. We just can't help ourselves. It's called a "confirmation bias" - meaning we give greater credence to evidence and arguments that support our beliefs and "disconfirmation bias" - meaning we argue harder and spend more energy trying to disprove arguments that don't support our beliefs.
It seems humans have other goals besides being right. Like, protecting our sense of self, to name one. Even when the evidence suggests we should change our beliefs.
So what do you believe?