Principle: All intuitions are extensive magnitudes.
Here Kant links the forms of intuition, space and time, to the categories of unity, plurality, and totality. In order for one to represent an object in space and time, it must be synthesized, i.e., a plurality of units must be thought together as a totality. Space and time themselves can be determined, or thought according to specific concepts (e.g., triangle, plane, etc.), through an act of synthesis, so any object which is represented as in space and/or time must also be subject to this synthesis. The resulting totality is a magnitude and is extensive. This means that in order to represent the whole or totality, the parts must first be represented. Thus the representation of an enduring state of myself (e.g., an hour's continuous hunger before a meal) is an extensive temporal magnitude, and the representation of a physically extended object is an extensive spatial magnitude, since all intuitions must be thought through the pure synthesis of space and time. Inner states can thus be quantified through numbers assigned to their successive temporal slices (seconds, minutes, etc.) and outer objects can also be quantified according to their temporal duration. Outer objects can in addition be brought under the laws of the quantitative science of space, geometry.