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• The first sign of a nervous breakdown is when you start thinking your work is terribly important.
  -- Milo Bloom...
• Since when is talking a sign of thinking?
• You're getting old when you stop to think and forget to start again.
• If you're ever stuck in some thick undergrowth, in your underwear, don't start thinking of what other words have "under" in them, because that's probably the first sign of jungle madness.
  -- Deep Thoughts by Jack Handey...
• When your friends begin to flatter you on how young you look, it's a sure sign you're getting old.
  -- Mark Twai...
• To give of yourself, you must first know yourself.
• The first sign of age ... is when you go out into the streets .
  .. and recognize for the first time how young the policemen look. -- Seymour Hick...
• If a loafer is not a nuisance to you, it is a sign that you are somewhat of a loafer yourself.