Prove a negative

Once an agency or politician accepts an assertion—and acceptance may come easily when a new program can be established or voters favor curried—the agency or politician can demand evidence to set the assertion aside, no matter how flimsy the evidence for it The demand cannot be met because it involves proving a negative. 

I heard a familiar sound. His Serenity sighed happily. How The man had a stroke, that s all. How can you prove a negative ... 

To classify alkaloids as waste products of metabolism implies that their formation has no further consequences for the plant, and in the strict sense of the term, this implication involves all the difficulties of proving a negative. Towards such a proof it may be pointed out that 90 or more per cent of plants appear to manage very well without ever forming alkaloids and that even those that do form them show no obvious abnormaliti when they are grown as alkaloid-free scions. The difficulties of the case become more apparent when it is realized that the full extent of alkaloid distribution is still uncertain, and that the scions may contain small amounts of alkaloid in their meristems. 

Equivalence trials Useful when superiority is unlikely to be demonstrated Scientific problem of proving a negative Large sample sizes Standards of care not previously studied... 

The challenges that remain are in actually proving that releases absolutely cannot occur (given it is hard to prove a negative and such data are scarce) and that all potential core damage states are either avoided and/or adequately cooled. The methods used include SA analysis codes structural failure mode analysis radionuclide transport in buildings and the environment historical geotechnical, hydraulic, and seismic response analysis and PRAs. 

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