We are all of the same species, and therefore share a good deal of requirements. Shelter, food, water, etc.
At the same time we have a couple other things that help to create differences between us:
1.
Genetics
We're a mix of our mothers and fathers. We share most of our genes with them, but at the time some variation. Those variations control minor differences such the color of our hair and eyes, to major ones when it comes to birth defects etc. The process of evolution ensures these variations continue on, and will always be there.
2.
Society
As a species, we've laid claim to the land on Planet Earth. This land is broken up into Continents, and then Countries. Countries are further broken down into States, Counties, neighborhoods, etc. In order to keep a form of equilibrium, we have written a standard way we should act, and what personal responsibility means within our society. We internalize this, and it becomes our culture. Once internalized, it can be more difficult to change than most attributes. We're tribal, and we don't like to be cast out.
Countries have their own cultures, and their people will have their own ideas. Some are similar, such as the US and the UK, while others are very different. From the consequences of actions (such as theft, which can get you anything from a fine in one place, and death in another), to religions, etc. Our culture becomes, largely, who we are.
3.
Upbringing
And then there is the fine tuning of our upbringing. We come into this world not as sinners, but as, essentially, clean slates. We can be loved and nurtured and brought up to show respect, kindness, and empathy, or we can be brought up to be mercenaries and killers. Our brains, and our temperament, and our idea of acceptable behavior is largely learned as we grow. We can be elevated through life by our upbringing, or cursed with chains and pain.
I could go on, but as usual, I'm wordy. I think the answer is, we're more the same than different, but the devil is in the details.
