For similar reasons to the "time value of money" concept, books read now are worth more than books read in the future. e.g. reading GEB at 20 and having it chan

For similar reasons to the "time value of money" concept, books read now are worth more than books read in the future. e.g. reading GEB at 20 and having it change the course of your life to become a Computer Science Ph.D. is very different from reading it on your death bed. Moreover, 3000 books is still only scratching the surface of all non-fiction ever published in English (let alone other languages), so strong heuristics will still be needed.