> Still, I am discomforted by your book-buying habits; a book unread is a valuable resource wasted :) But each to their own way.

There are lots of fantastic books out there, and only so much time to read them. Sometimes I buy some with the intention of reading them later. But reading books properly takes time, so it's inevitable that I fall behind.

Also, lots of the techincal monographs I buy have some overlapping contents with others I own.

I can buy a book for a single chapter. That's the only way to get that chapter, so it justifies the purchase to me, even if the subjects covered overlap with other books I own.