Referring to his unauthorized use of material for his major "Histoire(s) du cinema" Jean Luc Godard said in an interview in 1996:
For me there's a difference between an extract and a quotation. If it's an extract, you have to pay, because you're taking advantage of something you have not done and you are more or less making business out of it. If it's a quotation--and it's more evident in my work that it's a quotation--then you don't have to pay.
Of course, copyright does not make this difference (yet). But this was mid 1990s, and times were different. The first two episodes in Godard's series, each of which lasts 50 minutes, have been shown on five separate state-funded European TV channels without any permission from the copyright holders. It's hard to imagine this happening today.