Quite legitimately, different people have different notions of what is fair, and what is the right balance between fairness and efficiency.

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And by ignoring her right to do so, by reducing her freedom, the Court also revealed an astonishing lack of respect for the efficiency and fairness of free markets.

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Experts say flat tax models, such as the plan put forward by Mr Perry, are usually favoured by those hoping to increase efficiency and fairness in the system, while reducing complexity.

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Moving away from defined benefits to defined contributions in Medicare would greatly enhance the efficiency (and arguably the fairness) of the program, preserving it for future generations.

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One looks through the lens of efficiency and another through the lens of fairness.

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But if the efficiency argument is weak evidence, the fairness argument is assumed to make the case, and make it for zero percent taxation.

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