Washington (CNN) Ben Carson says President Barack Obama is a psychopath.

His comment came in an exchange between the neurosurgeon who's likely to mount a bid for the 2016 Republican presidential nomination and his chief adviser, Armstrong Williams, captured by a GQ reporter on the night of this year's State of the Union address.

Williams had said Obama looked "elegant" that night.

And Carson responded: "Like most psychopaths. That's why they're successful. That's the way they look. They all look great."

Later in the exchange, Carson accused Obama of knowingly selling the American public "a lie."

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