# Tome of Clear Thought *Wondrous item, very rare* ![](/Rules/Source/items/img/tome-of-clear-thought.webp#right) - **Weight**: 5.0 lbs. This book contains memory and logic exercises, and its words are charged with magic. If you spend 48 hours over a period of 6 days or fewer studying the book's contents and practicing its guidelines, your Intelligence increases by 2, to a maximum of 30. The manual then loses its magic, but regains it in a century. *Source: Dungeon Master's Guide (2024) p. 317. Available in the <span title='Systems Reference Document (5.2)'>SRD</span> and the Free Rules (2024)*