Pure Categories

Much of Kant is incredibly confusing, and when it seems like an idea has been explained well enough, something gets confused again. After this week’s discussion, I thought that I had a clear enough understanding of what Kant was trying to explain. However, after rereading some passages to write a blog post, one passage in particular became convoluted for me. This post is merely to ask for clarification on his point. 

On page 265, under B305, Kant pure categories and their possibility for transcendental employment. He writes:

“Since, then, as pure categories merely, they are not to be employed empirically, and cannot be employed transcendentally, they cannot when separated from all sensibility, be employed in any manner whatsoever, that is, they cannot be applied to any ostensible object. They are the pure form of the employment of understanding in respect of objects in general, that is, of thought; but since they are merely its form, through them alone no object can be thought or determined.”

By this does he specifically mean that someone cannot consciously apply the categories to objects and that the application is something that happens without one realizing it? Or does he mean that the pure categories are the form of understanding, and because of it, form everything that is in experience? Here, I am unable to know if I have an answer or am even asking the right questions.