Memorization is a learning based skill that helps you acquire additional Spell Stock from reading spellbooks. The general formula is put in the Spell Stock page, but in general, the relevant portion of the formula to Memorization is that your memorization + 100 is the multiplier on how much spell stock you learn. (100 Memorization gives you double spell stock per reading of a spellbook for any given current amount of spell stock you have and 900 Memorization gives you ten times the standard amount.) In Elona+, this skill has no effect on spell stocks gained from dreams.