Is our reality a need of the body or is it the illusion of the mind?

Somewhere along the line, everyone follows a certain line of reality. You can see it everywhere. Patterns. How people live with each other. Religion. War. People are so similar all over the world although we live separate lives. We live together with rules and laws as a collective. Is this reality indoctrinated into us or does something in our biology create this drive in the first place?