In terms of your question: If the person you are thinking of was completely normal before the head trauma, had serious head trauma and has been out of touch with reality ever since -- which is really the definition of psychosis -- then it is extremely likely that the head trauma is the cause of the problem.

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"His treatment met the legal definition of torture, " Susan Crawford, then head of the convening authority of military commissions, told The Washington Post.

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The feeling that the top of your head has been taken off, a definition of what makes a quote quotable that Shapiro takes from Emily Dickinson (who took it, basically, from Kant and Burke, who took it from Longinus a nice example of the sociology of quotation), is a feeling that readers of poetry expect from every poem they read.

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