Vocabularies for events, people, places....

• a single vocabulary for events cannot convey all the information we would like to have about events, people, places, documents
• ...and shouldn't try to
• experts in any particular field are probably the best people to write vocabularies for that field
• agreement on vocabularies takes lots of time
• agreement with experts from different fields takes even more time

Much better is to be able to combine vocabularies easily and devolve the creation of vocabularies where possible.