Do belief systems divide or unite us?

Different opinions can lead to a healthy debate and generate better ideas. However, holding strong beliefs can be detrimental to an individual & the society at large. We are all a product of our environment, so finding a common ground with another individual opposite to oneself, is always a good starting point. People will always hold different opinions/beliefs - It's a fact of life.

It can be summed up this way: For every belief that you hold, there's another individual holding the exact opposite. So yes, this can be a bit of problem.