This question is a conundrum of intricacy for philosophers around the globe and through the ages. I respect these people to much to describe an answer just like that out of the blue. I can honestly say that I haven't nearly researched this topic as deeply as I would want to, and I feel it would be an insult to thinkers everywhere if anyone including me gave an answer to this topic with little knowledge to back it. But I can within my power attempt to simplify this topic to its most basic form, this will offer me the ability to analyze the information at its base with minor influence from outside information. A topic like this though I will take slowly (no need to rush, no gun pointed to my head). So I will just pose some questions.
I want to ask first how does one produce an opinion? Is it through their senses and experiences? For my second question I want to ask what it is that determines what is fact? In other words what are the components or variables which allow something to be factual (this is a good argument for what is truth as well)? Answer these first and then we may delve deeper into this topic.