Related:

• Algebraic symbols are used when you do not know what you are talking about.
  -- Philippe Schnoebele...
• Algebraic symbols are used when you don't know what you're talking about.
• Do you know what you're talking about?
• There's no sense in being precise when you don't even know what you're talking about.
  -- John von Neuma...
• You don't know what you're talking about, do you?
• There's no use being precise about something when you don't even know what you're talking about.
  -- John von Neuma...
• You know you should be swimming when . . . Everybody's talking about "fin de siecle" and you keep looking for the fin.
• Green's Law of Debate: Anything is possible if you don't know what you're talking about.