Cowen is an economist, and many of the early linkers were economists as well. The lists contained many economics books, of course. I was surprised at how many philosophy and political philosophy books appeared on the economists’ lists. And how few–none on most lists–science books of any field or any modern books of ideas appear. From the lists of books, their minds were untouched by the ideas and incredible gains in understanding the world that flipped society upside down several times in the 20th century.
To jump to a wild conclusion, this may be one of the reasons the field of economics is so screwed up. Economists come to field field by way of philosophy and think ideas mixed with some mathematical modeling leads to discoveries about how real societies work. And these are people without any practical knowledge–no science, no engineering, no business experience, no government experience. Not even science at an undergrad level, or a widely read enthusiast. They think philosophy contains the essential ideas, and all the more applied fields are derivative, and so they have set their economics on a sound foundation.
Also, Ayn Rand is an important influence on many, which is not surprising but good for a few giggles. Also, Fight Club by Chuck Palahniuk is gaining as the influential book for libertarian minded young men. Watch out Ayn!