`  == The sense in which the word variety is employed (. . .) ==  The following statement is not offered any explanation in the article: ``The word ``variety`` is employed in the sense which is similar to that of manifold``. This appears to be grammatically incorrect, but I don't know how to fix it because I don't even know what it's trying to say! Is it merely saying that a variety is a similar object to a manifold in some sense? If so, this is a terrible way to express it. I am sure that any native speaker of English who doesn't already understand what this statement is trying to say will be confused by it. Would anyone care to explain?   `