Sometimes you can distinguish between primary and secondary sources easily, e.g. if you talk about a book this book is the primary source and everything else is

Sometimes you can distinguish between primary and secondary sources easily, e.g. if you talk about a book this book is the primary source and everything else is not. Sometimes it's harder to get to primary sources, but it's generally not hard to get close enough. If you analyze who copied what from where you can find out fairly easily which sources are close to what is reported and which ones are remote and part of the "whisper game." In my experience, almost everyone who criticizes media tends to offer no reasonable substitute for e.g. news agencies who have reporters on the ground. Mostly they refer sources that are far removed from the action reported (e.g. blogs, commentators, etc.) and therefore unreliable. It's not bad advice to seek primary sources in this looser sense, such as sources with reporters in direct contact with eye witnesses. On a side note, reporting biases are normal and not a substantive problem as long as people can recognize the reporting of alleged facts and distinguish these from opinions and comments. You can test this ability.