Abstract
Analysis of the doctrine of the notion may begin by differentiating the notion in Berkeley from the idea. For Berkeley "human knowledge may naturally be reduced to two heads, that of ideas, and that of spirits." These two objects of knowledge are so radically different from one another that they have nothing in common but the name "being." Concerning the first kind of knowledge, knowledge by ideas, Berkeley recognizes two kinds: "ideas actually imprinted on the senses" and "ideas formed by the help of memory and imagination." Ideas of imagination and ideas of sense "equally exist in the mind," i.e., they are both mind-dependent and distinct from the mind. Ideas of imagination are copies of ideas of sense