Book reading

Every book has three parts- part one contains what you already know, part two is what you need not know, it is only part three which you need to know and must read. This is what Justice Hidayatullah advised students of Aligarh Muslim university while delivering a convocation address four decades ago.This he had learnt from a class fellow in England with whom he was competing for 1st position.
I have been practicing this theory from the day I heard the speech and was convinced about its correctness till recently. I purchased a book for almost Rs 1000, tried hard to find 3rd part but failed, could not give up as I had invested Rs 1000, so started reading from cover to cover 1100 pages.Theory in which I believed in for 4 decades became doubtful as the book I read had only one part, the part I never needed to know.