The concept of normal can be measured in many ways.
1. It can reflect what the standard accepted behavior is for a majority of people within a given context. This view falls apart when you consider the acts of the Nazis hardly being normal.
2. It can reflect what the standard morees were in a previous time period. This somehow seems unfair to newer generations though.
3. It can be purely subjective and reflect the accepted behavior of a particular individual. This is most problematic. I'm sure Jeffery Dahlmer felt that "finger" foods were normal for him.
4. There can be a written code or constitution that one looks to for measuring normalcy. Our own Supreme Court sometimes overturns the will of the majority because they deem it "abnormal". This seems to exclude minorities unless all have agreed on the original code or constitution.
For example, some people may see a glass as half full. Others may see it as glass half empty. Still others my protest the irrelevance and say that the glass is not sanitary because I pissed in that glass. Is that normal?
So in closing, each person may chooose his brand of normal but that does not necessarily mean that the most popular one is the most normal one. Right now I'm beginning to wonder how normal I am for having spent so much time on this subject. But then again, I normally question my own motives when doing things just for fun. ;-)