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• There are three kinds of researchers: Those who can do math and those who cannot.
  -- Tom Rusk Vickery...
• My grandfather once told me that there are two kinds of people
  hose who do the work and those who take the credit....
• There are four kinds of people: those who sit quietly and do nothing, those who talk about sitting quietly and doing nothing, those who do things, and those who talk about doing things.
• H. L. Mencken's Law Those who can -- do. Those who cannot -- teach.
  Those who cannot teach -- administrate. (Martin's extension)...
• Those who can, do. Those that can't criticize.
• H. L. Mencken's Law: Those who can -- do. Those who can't -- teach.
  Martin's Extension: Those who cannot teach -- administrate....
• Those who can, do. Those who can't, teach. -- H. L.
  Mencken's Law Those who cannot teach -- administrate. -- Martin's Extensio...