normative propositions

While I don't know if this is the right forum for this, I stumbled upon a short argument of David D. Friedman regarding normative propositions (http://www.daviddfriedman.com/Libertarian/My_Posts/My_View_of_Oughts.html). He argues that morality can be perceived through some kind of '6th sense' like hearing a sound or seeing an elephant and that most people would agree on certain simple cases like 'having fun while torturing small children is bad' without being able to tell you why exactly this is should be an objective truth. So I was wondering if there is any data about a survey on this topic where one can see that people tend to agree on simple cases and disagree on more difficult ones (like people would agree that there is a computer I'm writing on, but not always agreed that the earth was rotating around the sun, simply because it was not as obvious). This argument isn't new of course, but while wrinting a paper for philosophical class about objectivism this question plopped in my mind.