P28: The Striving, or Desire, to know things by the third kind of knowledge cannot arise from the first kind of knowledge, but can indeed arise from the second.

Dem.: This Proposition is evident through itself. For whatever we understand clearly and distinctly, we understand either through itself, or through something else which is conceived through itself; i.e., the ideas which are clear and distinct in us, or which are related to the third kind of knowledge (see IIP40 S2), cannot follow from mutilated and confused ideas, which (by IIP40 S2) are related to the first kind of knowledge; but they can follow from adequate ideas, or (by IIP40 S2) from the second and third kind of knowledge. Therefore (by Def. Aff. I), the Desire to know things by the third kind of knowledge cannot arise from the first kind of knowledge, but can from the second, q.e.d.