The core of crude occurrence is merely certain patches of color. The precept as filled out with images of touch becomes an object, which is supposed physical; the percept as filled out with words and memories becomes a perception, which is part of a subject and is considered mental. The percept is just an occurrence, and neither true nor false; the percept as filled out with words is a judgement, and capable of truth or falsehood. This judgement I call a judgement of perception. The proposition knowledge is perception must be interpreted as meaning knowledge is judgement of perception. It is only in this form that it is grammatically capable of being correct.p. 154.