I wouldn't invest my time in finding the source code on this one. As you suggest, it has been doing the rounds for a while....perhaps because many are convinced of the purport. The veracity then becomes quite secondary.
Sent: Saturday, November 26, 2016 12:16 PM
Subject: [IAC#RG] Demonetisation - alleged Quote from Chanakya's Artha Shastra
Rear Admiral (Retd.) Mahendra Taneja
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When Mamata Bannerjee, Shiv Sena leaders, Kejriwal and other people are protesting against Demonetisation move of the PM, I am reminded of a famous quote by Chanakya( Kautilya ) in his Artha Shastra.
"Learn that when thieves, dacoits, traitors in the country become restless, shouting and trying to create anarchy; then believe that the King is ruling well"
Since our learned and scholarly list moderator is unable to locate the source of this famous quotation (which is also doing rounds of social media for past 6 days) in the nowadays "standard" reference of R. Shyamasastry's Arthashastra, perhaps there is some mistranslation in your version, and you can assist us by locating its source from which you were reminded.
You are doubtless aware that the real Artha Shastra of Chanakya is "lost" for centuries now and only available to certain Pandits of Kashi, and what was allegedly "rediscovered" in 1907 (coincidentally by the very same Shyamasastry) is a poor forgery.