Exactly what I was thinking. A search engine with "author:" and "topic:" refinements to contrast the writing of various folks on some topic or in reaction to

Exactly what I was thinking. A search engine with "author:" and "topic:" refinements to contrast the writing of various folks on some topic or in reaction to some event. I'd love to scan through a combined timeline of posts, essays and quotes comparing several folks - something like Google trends that is "source aware".