Were I a gambling man, I'd be willing to bet that the downvotes were due to people not knowing what "ceteris paribus" means and not bothering to look it up. If you remove that from your statement, it seems like something most people here would disagree with. However, several people have suggested in the comments that they agree with your statement:
I find the value of a quote to be almost completely independent of its originator.
the value of an idea shouldn't depend much on the author
(emphasis added).
These quotes suggest to me that people put some weight on who the author is, which presumably either implies your statement, or a statement that ceteris paribus, one prefers quotes from people who don't have those qualities.
I (rather stupidly) thought [i]ceteris paribus[/i] was a user MichaelBishop was replying to, since I only happened to see this in recent comments.
But having looked it up, it doesn't change my mind--I don't see how it can apply: the whole point of a quote is that it is unique, therefore all other things won't ever be equal...
(Since there didn't seem to be one for this month, and I just ran across a nice quote.)
A monthly thread for posting any interesting rationality-related quotes you've seen recently on the Internet, or had stored in your quotesfile for ages.