> > But if you write it like "science fiction", then that would mean that you write the other genres like "western", "romance", "mystery", etc., without the capitals. And that seems strange to me.

Of those four, I'd only capitalise "Western", because it's not about "the west", it's about "the West", a particular region of the USA at an particular point in history. Capitalising any of the others looks wrong to me. I suppose I could capitalise "Romance" novels if it meant novels written in one of the Romance languages.

Brunnen-"loves that wonderful Convention of previous Centuries in which all Nouns were capitalised"G