&gt; How are Wikipedia articles kept consistent with each other?<p>They aren&#x27;t.  There is no transactional&#x2F;referential integrity on Wikipedia.  When someone famous dies a pretty common pattern is that first the death date is added, and then in a later subsequent edit someone gets around to changing the present tense verbs into past tense verbs (&quot;Prince <i>is</i> a singer...&quot; --&gt; &quot;Prince <i>was</i> a singer...&quot;).<p>I can tell you all about how category normalization is maintained, though.  It starts with this process: <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Wikipedia:Categories_for_discussion" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Wikipedia:Categories_for_discu...</a>