> Why should it be different if the causes are more complex and harder to trace back?

Because if you go that far you deny the whole concept of individuality and humanity even, up on which all of our moral and legal system were built. What are we but cogs in a machine?

It's not that there isn't any logic in it, it's just not an useful thing to contemplate about while you obviously still cling on to your sense of self so far as to having an argument with others.