Tome of Understanding

Tomes of Understanding are magically tomes that increase the primary ability of wisdom by one point and are consumed when the point is added. One tome of can be found during the quest to rid yourself of the poisoning from Marek. Another one can be found in the Underground passages of Candlekeep and more can be found in Durlag's Tower.

In-game description
"A typical tome of understanding contains a sober, if dry analysis of legal battles, historic events, government policies, philosophical treatises and theories of magic and metaphysics. While rarely interesting to anyone outside of their already well-educated niche market, it is said that some such tomes have even added a single point to the Wisdom of certain half-gres. Such marvels, however are the product of a potent magic placed upon the tome as it is being written. Unfortunately, the same magic causes the tome to dissapear after a single use."