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By Martin Gardner

Test with cryptography—the technology of mystery writing. Cipher and decipher codes: transposition and polyalphabetical ciphers, well-known codes, typewriter and mobile codes, codes that use cards, knots, and swizzle sticks...even invisible writing and sending messages via outer house. Hours of intrigue and problem. forty five diagrams.

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Extra info for Codes, Ciphers and Secret Writing (Test Your Code Breaking Skills)

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In trying to deal with such pressures, it is most often the analyst personally who has to suggest corrective action and, at the same time, try to find “acceptable” ways to inform the client of the rationale for effecting change to his original directives. The message that deserves reinforcing here is simply that the model is a useful and highly adaptable framework for tackling any strategic analysis or research project. It requires careful planning to implement properly and effectively, and yet it is flexible enough to handle strategic issues, whether they be in law enforcement or any other analytical environment.

Conversely, when it comes to more coordinated requirements for intelligence involving multiple targets and perhaps multiple jurisdictions, enforcement practice is to continue the reversal of military terminology and call it tactical (instead of operational). Even so, enforcement agencies rarely seem to take to this term tactical easily or comfortably, since it has little relevance to the way they naturally describe their activities. Instead, its use seems to be based on an acceptance that there are three tiers of intelligence, two of which—operational and strategic—have already been labeled, and thus the remaining category needs to be given a separate label: tactical.

However, when the research requirement is accompanied by any strongly directive approach—most often from clients or managers who may be acting personally or, conversely, giving voice to institutional beliefs—this will suggest answers and so inhibit real analysis in favor of justifying views already held. This sort of action-andresponse cycle will almost always pervert the capacity of intelligence to produce proper research-driven outcomes. The analyst is in an invidious position in these cases: trying to meet the genuine expectations and requirements of clients and yet being expected to ensure that balance and a sense of perspective are maintained, avoiding being led to unwarranted conclusions merely because of the client’s prejudices.

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