Unique words as a function of worth

Question/Idea

What relationship do the number of unique words have to the quality of the work?

cc licensed ( BY SD ) flickr photo shared by bionicteaching

Inspiration

I was looking at syllabi from famous authors and saw a paper requiring 3,500 words. I went to WolframAlpha to see how many pages that was. After seeing it was about 14 double spaced pages, I clicked on the option to use “words” as a unit and got the image you see above.