A test of the most recent xkcd comic

I read the xkcd comic this morning like I usually do, but forgot to read the ‘roll-over’ text that Randall puts in. My friend Ryan pointed it out to me, and to quote:

Wikipedia trivia: If you take any wikipedia article, click on the first link in the article text not in parentheses or italics, and then repeat, you will eventually end up at ‘Philosophy.’ “

SO, I had to try it. and the page I started with was: ‘Mario‘ Links in order after that:
fictional character
representation
semantic
meaning
linguistics
human
taxonomically
science
knowledge
facts
information
finite
infinite
mathematics
quantity
property
Modern Philosophy
It worked! I tried it with a couple more, and they worked to.
I’m not exactly sure why this would work. Can anyone explain it to me?
[UPDATE: My friend Lianne found an exception…]
[UPDATE #2: Ryan fixed the exception… ]