Sometimes I start to think when I'm driving in traffic, or walking in a place filled with people, like a store.
Every car has people in it. Every store is filled with people. Every single person you see is living in their own worlds, living their own story. They are the main character in their story. They have to deal with conflicts and problems in their story. Their stories are filled with countless experiences. Who are you in their story? Could be as insignificant as a stranger passing by.

It's like seeing thousands of books all around you.

We are all living our own stories. We are playing the main character in our stories. As main characters, we all deal with conflict, and usually face several antagonists throughout our story. I think that's why people show compassion for each other. We realize we are not the main character in their story. That they also are facing problems, conflicts, and are just trying to make it through their story, just as we are.
Even animals and insects are living their own stories. I have respect and compassion for most life forms, because I feel like we are all similar, all just living out our own stories, dealing with our own problems.