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yCounter-argument:
xGene Spafford:  “The open-source movement is largely devoid of systematic efforts to guarantee security.  The fact that code can be examined for flaws does not mean it will be examined by anyone competent.”
yFunnier counter-argument:
xAlbert Einstein [quoted in “A Second Look at the Cathedral and the Bazaar”]:  “Only two things are infinite, the universe and human stupidity, and I'm not sure about the former.”
z