“Don’t speak about things you know nothing about” used to be a much easier maxim when the number of things about which you could speak was limited to a daily newspaper and three national broadcast television channels and when “know” merely meant possessing an adequate grasp of an agreed-upon set of facts.
Now we can know nothing about so much more.
YoRocko! 
We can indeed, Rocky. If that maxim were more widely known, wouldn’t the world be quieter?
That’s really funny