 The suggestion here is roughly this: if the representation of space were a concept rather than an intuition, one ought to be able to construct it by placing its parts together. This seems to require that it is possible to represent the parts independently of representing the concept to be constructed. This is the case with other concepts: it is possible to represent any of the parts of the intension of &lt;human&gt;, such as &lt;material being&gt;, without ipso facto representing the whole concept, &lt;human&gt;. Kant is claiming that this will not work in the case of the representation of space because we obtain the representation of places only by delimiting some subsection of our representation of the one all-encompassing space. To put the point in a way that highlights a parallel with the first argument of the Metaphysical Exposition: the representation of any place presupposes the representation of space. Thus we cannot represent any of the “parts” of space—any place—without ipso facto representing space itself. The idea, then, is that the part-whole relation of the representation of space is distinct from the part-whole relation that obtains for concepts.