Both strategies (empathetic and sociopathic) can be selected for; they're relatively stable when combined. The sociopaths need empathetic people to prey on, the empathetic people can tolerate the cost -- up to a point, at which they cooperate to attack the sociopaths.
You might fairly characterise civilisation as the arms race between sociopaths and everyone else.
You might fairly characterise civilisation as the arms race between sociopaths and everyone else.