It is impossible to make anything foolproof, because fools are so ingenious.

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• Murphy's (Fourth) Corollary:
  It is impossible to make anything foolproof because...
• It is impossible to make anything foolproof because fools are so ingenious.
  Murphy's Second...
• Murphy's Eleventh Law It is impossible to make
  anything foolproof because fools are so ingenious...
• It is impossible to make anything foolproof because
  fools are so ingenious...