When Johannes Gutenberg gave us the printing press in the 15th century, he also invented a suitable ink to go along with it. His ink was a glossy black, and the idea of printing books in black on white paper has remained ever since, because that is by definition the highest contrast you can get, hence easy to read. Millions of books have appeared since Gutenberg, spanning a huge range of subjects and world views, but they did not differ in ink color one bit as the centuries came and went.
Lately, however, I notice a worrying trend as I browse the shelves in the bookstores I frequent. A small but growing number of books are published in all sorts of smart-aleck color schemes. Ignoring the ones on colored paper – where the color schemes are intentionally artsy – we see books in gray ink, blue ink, brownish ink, all on white paper. And not just a sidebar or special page; the entire book is printed this way, as if the publisher said to himself “Hmmm… how can I improve the reading experience? Ah! Let’s use a lower contrast ink than we might. Sure, gray ink may cost more than the standard black, but what’s a little money compared to the pleasure of giving my readers eye strain headaches?”
Bad, bad idea. Give us books in good old black on white!