I got into a discussion over lunch today about the over-reliance of Wikipedia as a factual source of information. I pointed to the fact that verifiability is one of the online encyclopedia's core content policies, but how "verifiable" are some of the sources used on Wikipedia?

To answer this question, you first need to agree on the definition of verifiable. Having looked at both British and American dictionaries, the key element seems to be something that is capable of being tested by experimentation or observation. But is this the same as the truth?

Well according to most thesauruses (or should that be thesauri) the antonym of verifiable is falsifiable, so my conclusion is that it is. This is further confirmed by the definition of the stem word, verify, which is widely agreed to mean to prove, determine or test the truth.

Back then to Wikipedia's verifiability content policy. Lo and behold, right at the top of the page we see:

The threshold for inclusion in Wikipedia is verifiability, not truth-that is, whether readers are able to check that material added to Wikipedia has already been published by a reliable source, not whether we think it is true.

So the Wikipedia definition of verifiable does not include any test of truth.

But wait. There's something else in that extract from Wikipedia's verifiability policy. According to them, the test of whether something is verifiable or not is whether readers are able to check that material added has already been published by a "reliable source", a term that Wikipedia further defines as "reliable, third-party published sources with a reputation for fact-checking and accuracy". In a footnote to this the word "source" has three related meanings to Wikipedia: the piece of work itself, the creator of the work, and the publisher of the work. It goes on to state that "all three affect reliability."

On the basis of this information, I have no option but to concede to my lunch companion that Wikipedia is indeed over-used as a source of fact.

Do you agree?