Because the EPG and Ex2 Core rules for thaumaturgy are too costly, too complex and too lame for use by Exalted. They may work fine for mortals but most characters aren't mortal so there need to be rules that take into acount the weakness of thaumaturgy for Exalted who have Charms and Sorcery at their beck and call.
Thaumaturgy is seperated into Sciences. The most common of these are the Science of Warding, Enchantment, Weather-Working, Alchemy, Divination, Summoning, Geomancy, Animation and Naming. Learning these Sciences encompases the knowledge of the rituals and pratices that are involved in the actual use of the magic. It does not involve any knowledge related to the use, side-effects, legality or other consequences or context of the magic. That is the province of the Occult ability.
Each Science is a background, rated 1-5. These Sciences are purchased at 3 XP for the first dot and CRx1 for the later dots. Certain sciences are Complex, covering a broader area then others and taking more effort and know-how to master. The bits that make up a Complex Science, each potion in Alchemy and each type of Warding spell, are called Knowledges.
Every dot of a Complex Science that a character has automatically grants them Knowledge of 1 knowledge. Additional Knowledges can be purchased for 1 XP. Certain Knowledges have a minimum associated with them. Without at least that many dots in the Science, the Knowledge can not be put to use. The character lacks the power to use it properly.
Roll: Int+Occult
Cost: 3 motes + 1 WP per roll
Time: 1 day per roll
Knowledges: Fair Folk, Ghosts, Lesser Demons (3), Greater Demons (5), Lesser Gods (3), Greater Gods (5), Lesser Elementals (3), Greater Elementals (5), Half-Breeds, Beastmen, Wyld-Touched, Undead, Sorcery-Spawn (2), Automata, Animals
Notes: Refer to the EPG for full descriptions of each level. Page 143.
Notes: Refer to the EPG for full descriptions of each level. Page 149.
Notes: Refer to the EPG for full descriptions of each level. Page 148.
Roll: Int+Occult
Cost: 3 motes + 1 WP per roll
Time: 1 day per roll
Notes: Each dot of Alchemy grants knowledge of one potion. Additional recipes can be purchased for 1 XP each. Recipes have a minimum required Alchemy rating listed with them.
Notes: Refer to the EPG for full descriptions of each level. Page 136.
Knowledges: Pyromancy, Stone Throwing, Astrology, Bone Casting, Crystal Gazing, Anthropomancy, Reading Entrails, Water-Gazing, Scrying
Roll: Cha+Occult
Cost: 3 motes + 1 WP per roll
Time: 1 hour per roll
Knowledges: Fair Folk, Ghosts, Lesser Demons (3), Greater Demons (5), Lesser Gods (3), Greater Gods (5), Lesser Elementals (3), Greater Elementals (5), Half-Breeds, Beastmen, Wyld-Touched, Undead, Sorcery-Spawn (2), Automata, Animals
Roll: Int+Occult and Int+Crafts
Cost: 3 motes + 1 WP per roll
Time: 1 week per roll
Knowledges: Revoking, Animation, Shaping, Repair
Notes: System Forth Coming. Based on Effigy (Ushabti) from Mummy the Ressurection.
Roll: Int+Occult
Cost: 5 motes + 1 WP per roll
Time: 1 minute per roll
Notes: System Forth Coming. Based on Nomenclature from Mummy the Ressurection.