This can be contrasted with Schopenhauer's opposite teaching that concepts are derived from perceptions, this being the very reason why pure concepts, or categories, require schemata.
Concepts are derived from perceptions. Concepts were being the very reason why pure concepts require schemata. Concepts were being the very reason why categories, require schemata. This can be contrasted with Schopenhauer's opposite teaching this. Perceptions are this.