Another way of looking at it...
Is to apply the scientific method.
In order for a theory or hyptothesis to be valid, in must be in accord with real world observational data.
In this case, some of the observational data does not conform to Goldberg's theory. But there's more.
This is not just any observational data. No, the Whitewater/Lewinski affair is the defininitive real-world study of bias in the media done over the last 20 years, as it amounts to the largest American political scandal during that period as reported by these same media.
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