Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: spirits can produce such manifestations or how it is possible for them to do so. Locke's Theory Of Human Understanding. The reasoning of Locke's theory is as follows: Reality is constituted of three different kinds of things with their relationships. The three kinds of things are minds, ideas, and bodies. The mind is a receptive medium in which ideas arise by virtue of the operations of matter or body. Anything which is present to the mind is an idea. Ideas are impressions made upon the mind and are of two kinds: those caused by the primary qualities of objects and those caused by the secondary qualities of objects. A quality of an object is the power in it to produce ideas. The primary qualities produce ideas which copy them or resemble them; the secondary qualities do not produce resembling or copying ideas in the mind. The secondary ideas are mere perceptions in the mind; the primary are modifications of matter which cause ideas in us resembling them. It results from the nature af these two kinds of ideas that secondary qualities reveal to us nothing of the real object, while knowledge of primary qualities is "real knowledge," knowledge of "real existence." Knowledge is the perception of the connection of, and agreement or disagreement of, ideas. Thus the originals of knowledge are ideas of sensation impressed upon the mind by matter and knowledge is limited by the existence and nature of ideas. Thus Locke concludes his task. He sought the originals, certainty, and extent of human knowledge: he found its originals in the ideas; its extent in the limits of their relationships; and its certainty dependent upon the directness with which the mind perceives those relationships. The problem which Locke sought to solve was one of definition and origin. He asked: what...