>>/5548/
Yeah, I'd like to know too. I'm torn between "this kind of history-of-ideas is something that Google should be able to algorithmically trace" and "thank god we're not that legible yet".
Anyway, I'm certain that LessWrong was even first. I think the earliest usage of the term there was around 2009, while per Wikipedia
> In the mid-2010s, many users on internet forums and social media gave 'virtue-signalling' a pejorative sense when they denounced such empty acts of public commitment to unexceptionable good causes such as changing Facebook profile pictures to support a cause […]
and apparently the earliest known use is from 2004 (https://www.wordspy.com/index.php?word=virtue-signalling)
So maybe LW just picked up on something that was already in the air at the time.