As to character, the young Margaret Thatcher combined stubbornness, imperviousness and a sense of grievance.

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The individuals seeking drugs without violence or prescriptions would understand the imperviousness of sites like the agorist Silk Road.

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He embraced that quaint otherness, his imperviousness to fashion or fads.

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"If this is Kim Jong Il's welcoming present to a new president -- launching a missile like this and threatening to have a nuclear test -- I think it says a lot about the imperviousness ... of this regime in North Korea to any kind of diplomatic overtures, " Mr. Gates said.

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