Physical Nature of a Used Bookstore
Often when I survey my books I am reminded of a quote from the wonderful Terry Pratchett:
“The truth is that even big collections of ordinary books distort space, as can readily be proved by anyone who has been around a really old-fashioned secondhand bookshop, one of those that look as though they were designed by M. Escher on a bad day and has more staircases than storeys and those rows of shelves which end in little doors that are too small for a full-sized human to enter. The relevant equation is:
Knowledge = power = energy = matter = mass;
a good bookshop is just a genteel Black Hole that knows how to read.”
– Terry Pratchett, “Guards! Guards!” Footnote, 8 p.
(It is interesting to note that the electronic versions of Guards! Guards! lack Pratchett's lovely footnotes. They are humorous and add to his books. Their exclusion is the worst form of literary villainy.)