Ben Evans once joked that Jeff Bezos was probably obsessed with an old encyclopedia of retail.
If you could look in the safe behind Jeff Bezos’s desk, instead of the sports almanac from Back to the Future, you’d find an Encyclopedia of Retail, written in maybe 1985. There would be Post-It notes on every page, and every one of those notes has been turned into a team or maybe a product.
— Benedict Evans, Amazon is a boring retailer.
Evans is making fun of the fact that most of what Amazon has done isn't innovative, but an extreme, technologically adapted consequence of what could be learned from a retail textbook. Thomas Aquinas' beware of the man of one book is the quote that usually comes to mind when people are said to be obsessed with one particular idea, and its most common interpretation is "you should read more".
But my take puts more emphasis on the word "beware": those who read few great books, but with focus, intensity and curiosity, are enlightened creatures that you do not want to oppose1. Jeff Bezos is a man of a single book. My interpretation is that you must be way more demanding about the things you read, so that you can be indulgent and patient with those that are worthy of your attention.
If Thomas Aquinas were alive now, I believe he would have said beware of the man of the social network.
San Isidro, Labrador de Madrid, writer Lope de Vega said "A noteworthy student is he, the man of a single book. For when they were not filled up with so many extraneous books, as they were leaving behind, men knew more because they studied less."↩