People have one thing in common: they are all different.

Related:

• All sweet things have one thing in common ...
  a tendency to make you sick. --...
• What is the one thing that all men at singles bars have in common?
  They're married...
• To know only one thing well is to have a barbaric mind:
  civilization implies the graceful relation of all varieties...
• One thing Jimmy Swaggart and his wife have in common that most married couples don't.
  her clothing...
• Common and vulgar people ascribe all ill that they feel to others;
  people of little wisdom ascribe to themselves; people...
• The remarkable thing about Shakespeare is that he really is very good,
  in spite of all the people who say he is very good...
• Common sense and a sense of humor are the same thing,
  moving at different speeds. A sense of humor is just...