To me there is a very big difference between where our ethical beliefs come from and where they should come.  Our ethical beliefs come from our environment that we have grown up in and the people around us.  They are formulated from a very young age and are developed as we go on.  Where our ethical beliefs should come from relates to religion and what is said in the scripture of the religion we follow.  The difference between these 2 is that where are ethics come from are often shaped and altered to better fit our lives, where as where our ethics should come from are often a better fit for living back when the religious text we follow was written.