[Spoilers] How did Voldemort learn the horcrux spell?
[HPMOR related] This question has always bugged me. The interdict of Merlin stops spells being learnt from anything but a living mind. Yet Tom Riddle is specifically said to have learnt the horcrux spell from a book. Why are there even spells in books? Who would believe the ritual for...
Guvf qbrfa'g jbex. Fvapr yngre ba jr yrnea gung lbh pna'g fraq nal vasbezngvba onpx zber guna 6uef, vg frrzf zber yvxryl gung Qhzoyrqber jnf hfvat gur pybnx gb genvy Uneel sbe gur ragver qnl (naq nyzbfg pregnvayl ba gur genva, naq creuncf rira va qvntba nyyrl).
Juvpu zrnaf gung qhzoyrqber, va gur pybnx, jngpurq uneel, va gur pybnx, uryc uneel orsber ur tbg gur pybnx naq xarj ur unq gb tb onpx 6uef gb rafher gung uneel tbg gur pybnx 5uef rneyvre.