For decades, he took Stelazine, one of an old class of antipsychotics that controlled his paranoia and delusions but also left him with muscle spasms that contorted his body.

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Loughner was initially deemed unfit for trial because he suffered from schizophrenia and delusions, but that ruling was reversed after more than a year of treatment in prison.

BBC: Gabrielle Giffords in March 2013

But the causes of his delusions are as irrelevant as they are unknowable.

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But while Sandusky clings to delusions of a successful appeal, there is a very real and significant fallout for the school he left in shambles.

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The point of the legend is not that Canute had delusions of grandeur, but the opposite.

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The opening parade past applauding locals on the streets of Coleraine induced delusions of grandeur, but that was topped by hearing your name booming from the tannoy as the teams were announced before the opening game in Castlerock.

BBC: SPORT | Football | Irish | Only the cream for Milk Cup

Nice to know, but not the kind of thing requiring delusions.

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But his hopes of a comeback may not be delusions.

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Very popular opinions, but are they accurate assumptions or merely, as Charles Mackay wrote in 1841, extraordinary popular delusions?

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