Old Books, New World

Recently I was asked what the oldest book in our library was. I didn't have an immediate answer, nor was I sure how to go about finding out. I employed a variety of search techniques, including browsing through the rare book stacks, all the while focusing on religious books, which I figured would be the most likely candidates. Finally I came across a small book printed in 1641. I can't say for certain that this is the oldest book in the collection, but it is definitely one of the oldest.
While we might refer to it as the "Passionate Remonstrance" for short, its extended title is, with some liberties in spelling and capitalization, "The passionate remonstrance made by his holiness in the conclave at Rome: Upon the late proceedings, and great covenant of Scotland, etc., with a reply of cardinal De Barbarini in the name of the Roman clergy." The work is bound, as indicated on the title page, "together with a letter of intelligence from the apostolic nuncio (now residing in London) to Pope Urban VIII."

This 80-page satire, which vilifies the Scots for turning away from the Church of Rome, is usually attributed to the English pamphleteer Richard Overton (d. 1664). I had never heard of the book or the author before, but then I do not study the 17th-century Scottish Church. In my efforts to discover something more about the book, I found that a print-on-demand version, based on a digitization of a 1646 printing, was available from Lightning Source through Amazon for under fifteen dollars. In this brave new world of universal access, knowing what I know now, can I really justify keeping my copy on the shelf?