User blog comment:Semanticdrifter/Understanding Fair Use/@comment-1474707-20121128132007/@comment-4811793-20121128142122

The point I was trying to get at is that the more an article adds to or transforms the original material, the more likely it would be considered fair use. Let's say you have an article about Game of Thrones. Copying the entire first chapter word for word and then inserting only two or three words at the end would almost certainly fail a fair use analysis. However, writing an original 900 word in-depth character study of Eddard Stark that analyzes his role as executioner and noble duty in fantasy literature and including a brief quote to illustrate the point would be much more likely to be a fair use.

The more the article could theoretically exist on its own, the more likely it is that the copyrighted material is not the heart of the article but used in a complementary way.

Using copyrighted material only when necessary to aid understanding is a sound policy and looking for free alternatives can certainly reduce the amount of risk associated with guessing at fair use.