opinion or fact?

In the middle of an argument the other day (i think with my father... We are living with them until we can move into our new house on the 1 March. Makes for some tension!) i realised that the line between opinion and fact is rather blurry in our minds.
We assume our own opinions are fact.

Opinion according to dictionary.com is

1. a belief or judgment that rests on grounds insufficient to produce complete certainty.

2. a personal view, attitude, or appraisal

 

Wheras a fact is

1. something that actually exists; reality, truth

2. a truth known by actual experience or observation; something known to be true

 

I guess the difficulty here is that we often believe our own opinions are the TRUTH. But they arent necessarily because they are not proven! But to an extent they do exist for us and are the reality.

 

The problem with having such fixed ideas about our own opinions is that it makes us closed minded and not able to change our minds. But thinking back to my own argument i guess i dont always want to change my mind or listen to a different opinion to mine.

 

A personal challenge (for my self firstly) is "am i prepared to not hold so closely to my opinions that i could changew my mind? am i prepared to accept that my opinions are not necessarily the truth?"