An old proverb has it that "if the thorn doesn't scratch when it first emerge, it will never scratch."

有一句古老的谚语说， “如果荆棘刚长出时不扎手，那么它就永远不扎手。”

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We can never start from scratch.

FORBES: Charles Johnson on Free-Market Anti-Capitalism

On the most mundane level: scratch-proof glass and tiles that shed dirt and never need cleaning.

FORBES: Magazine Article

"The more remote the location, the more I scratch my head and say, 'They are never coming back, '" Mr. Forster says.

WSJ: Money Lessons From 'Downton Abbey'