Letters and manuscripts have, besides their obvious historical and aesthetic value, a pretty clear economic value. The first example the author cites is a singl

Letters and manuscripts have, besides their obvious historical and aesthetic value, a pretty clear economic value. The first example the author cites is a single letter which went for over $500--not a fortune, but when applied to a whole mass of documents, not unreasonable to call a treasure. And again, that's besides their cultural value. You might never have seen them, but you could very well have seen information from them. Personal letters are the primary texts which historians and literary critics draw from, the sources from which we build up an understanding of the past. Their loss means more than a few random pages being scattered to the wind--it means we've lost a bit of knowledge of our own history.