Strict And Liberal

People understand instinctively that the best way for computer programs to communicate with each other is for each of the them to be strict in what they emit, and liberal in what they accept.  The odd thing is that people themselves are not willing to be strict in how they speak, and liberal in how they listen.  You'd think that would also be obvious. 

-- Larry Wall (1954 -), programmer, best known as the creator of the Perl programming language, "2nd State of the Onion", on Jon Postel's Robustness Principle applied to human communication