The world is so diverse.
Some people we like, some we dislike, some we find cool, some are weird. And the people we have feelings toward similarly have feelings toward the rest of the world (just like we do).
Why is it that the same event can cause so different reactions between two human beings? Why does one justify something that is downright wrong to another? Why do we think some people are weird? Why are some beliefs irrational and why are our beliefs rational?
We are all exposed to a series of stuff that affects what we think about something. This stuff is a collection of our personal experiences, observations (which are really just a part of our experiences) and our influences. These are extremely broad. Our influences comprise of a lot of things. People around us (friends, authority, random guy on the street), the information reaching us through our senses (books, TV, news), the cultures and stories we create—all these influence us. And when we look at it, even these things are quite dense and go deeper.
And then experiences are of course something that happens to you all the time. Every moment is a new experience. Good or bad does not matter. Each equally affects us; in the long run, the way we think is a collection of personal experiences.
This stuff shapes our worldview. We have a way of looking at things through the lens of all these past experiences and influences. This makes our mental character. Our long-term perspective. It certainly changes as time passes. But for the moment whatever we think about and do is thought of and performed through what this broad lens justifies.
Since everyone has different experiences, everyone has a different perspective. And that perspective shapes our minute-to-minute actions and thoughts. That’s why two people are found to have opposing views on the same subject.
That’s why when two similar people (in physique) share the same experience, for example both fall from a tree and fracture their leg. Same place, same type of fracture, same intensity. But one recovers faster, and one shows a different mental response that has an effect on the physical healing. And maybe one develops a strong phobia against trees and is scared of trees even when he doesn’t need to climb them. While we see the other one on top of another, this time taller tree just three months after his fracture.
Our fears, desires, reactions—all these are shaped by our perspective. They are different as they ought to be. It’d be quite boring to live in a world where everyone goes through the same life. But when this comes in the way of reality and truth, stuff matters.