If somebody describes herself as "not tall, not short, not fat, not thin", she is saying that she is of average height and weight. While it may seem cumbersome, this sort of indirect method of conveying information by elimination can sometimes be most efficient.
Bridge bidding systems, for instance, use "exclusion principles". There is a limited, though very large, number of possible bridge hands. Bidding conveys information about card distribution. It is often more efficient for a bidder to state that certain distributions are not held. That enables the partner to get a good idea of what the bidder does hold.
Exclusion is also an interesting way to analyse political statements. Narendra Modi, for instance, has never expressed any regret for what happened in 2002, and the lack of even a single statement to that effect has probably affected his career more than all the things that Mr Modi has actively said and done since Godhra.
Rahul Gandhi's recent speech at the Confederation of Indian Industry meet could be considered a mine of information because there were so many things left unsaid. Gandhi was directly addressing the shrewdest, hardest-headed and most successful people in India; indirectly, he was speaking to a global audience. He must have known that people would parse his every "hum" and every "haw".
The forum was ideal for laying out the details of concrete policies designed to foster faster and more inclusive growth. Mr Gandhi did not, however, choose to speak in concrete terms, or about concrete measures.
He did not mention the goods and services tax (GST). He did not touch upon the need for accelerating the passage of crucial economic legislation, stuck in Parliament for years. He did not acknowledge that the government must speed up clearance processes not only to enable faster infrastructure creation in future but to ensure that
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