Aspects (Thaumcraft 4)

Aspects are the various elements of the Thaumcraft 4 world that many objects in the world are made of. Aspects can be separated into 2 categories: primal and compound. There are six primal aspects: Aer, Aqua, Ignis, Terra, Ordo, and Perditio. Compound aspects are those that are combined by 2 primal and/or other compound aspects from a lower tier. In the case that an aspect is made from compound aspects of two different tiers, it will always be one tier up than the higher-tiered of the two component aspects.

There are 48 different aspects in the base mod, though mod addons can add more (e.g., Forbidden Magic). All aspects have their own type of Ethereal Essence, Mana Beans, and crystalline forms.