For most of us, video and written news are the sources we are most likely to deal with. It is very important to be aware that reporters often do NOT see all of what they report even if they are in the area. It is better to go straight to the horse’s mouth, which we can usually do for documents and expert testimony if not witnesses. It is also important to note that the words that accompany video footage, and how the video is edited, can very easily be misleading.
A comprehensive article on a subject or event will often reference several other sources. As obvious as it then might be to say Wikipedia can be useful for identifying multiple sources (although we absolutely must check those sources ourselves), many people stick to the sources that tell the story they want to hear. If we want to do better than that, looking at Wikipedia might be a start, since -all other things being equal– each extra source which agrees makes the given information more likely to be true.
If one person tells me they’ve seen a cow at the bottom of the high street, they might be lying or mistaken. If two people tell me separately, a few minutes apart, it’s not so likely they would both be mistaken. Perhaps they are in it together, conspiring to make me think there is a cow at the bottom of the high street when there isn’t. If ten people tell me, I’m probably going to think they aren’t all likely to be mistaken. They could ALL be in it together, but the more people involved then generally the more work required to keep up a lie. When it comes to whether there’s a cow in a built up area, why bother going to that much trouble to lie?
It also helps if the person telling us about the cow is known to be trustworthy. The information ideally will not conflict with other knowledge we hold either. If all cows on Earth were killed by nanorobots released by a mad scientist then it wouldn’t be very likely there was a cow anywhere.
Now, what if rather than a big lie deliberately involving many people, one person started a rumour about a cow on the high street and they told someone else, who told someone else, and so on, and then ten or more people told you? Then it doesn’t matter how many people tell you about the cow: It would all be coming from one person, either lying or mistaken. So in the pursuit of truth we need also to make sure that our sources are independent. That is, we need to know if they witnessed the cow for themselves without being influenced by others.
Lastly, if half the people we talk to say there definitely is a cow and the other half say, no, there definitely ISN’T, then who are we to believe? So conflicting accounts -as long as they are trustworthy, independent, and equally direct (e.g. two witnesses to the event)– rightly cause doubt.
To recap the features to look out for:
– First hand accounts and documents. Note that even a news piece contains much that is indirect and checkable.
– Trustworthy sources.
– Multiple sources.
– Independent sources.
– Agrees with what we already know.
– All things being equal, the story is likely.
– Not many independent conflicting accounts.
That’s the basics. Before we go into each of those in detail, it is of the utmost importance to deal with the one person who most gets in the way of finding out the facts. They will be the subject of Part 3.
 Wikipedia footnotes are clickable links which bring up citations, themselves usually clickable. If you’re not sure what a citation is or how to read one, here’s an explanation.
 All things aren’t equal, but we’ll come to that in good time.
 Fortunately, 80s pop icon Alison Moyet foiled the scientist and the only harm done was minor abrasions to two cows in a field in Letchworth.
 Citation needed.