An Essay Concerning Human Understanding - Book IV Summary & Analysis

This Study Guide consists of approximately 26 pages of chapter summaries, quotes, character analysis, themes, and more - everything you need to sharpen your knowledge of An Essay Concerning Human Understanding.
This section contains 1,112 words
(approx. 3 pages at 400 words per page)

Book IV Summary and Analysis

After having gone through an analysis of experience, ideas, and words, in Book IV Locke takes up the subject that he originally set out to investigate: knowledge. The setup is necessary as here Locke plans to give an account of knowledge based only on the concepts he has explained in the previous part of the book. An account of knowledge with no innate ideas and based only on the ideas generated from experience, or, as we would say today, an empiricist theory of knowledge. As Locke believes he has shown, the mind and its faculties of understanding have no other object than ideas, hence knowledge only consists of connections between ideas. We can only have knowledge of things that we perceive or could perceive. Given that knowledge only consists in certain relations between ideas, Locke believes those relations can be reduced to four kinds: identity and diversity, relation, necessary connection, and real existence. We will look at each of these forms of knowledge but before we do, we should give attention to Locke's notion of different degrees of knowledge.

Locke claims that intuitive knowledge is the clearest and the most certain of all kinds of knowledge. Intuitive knowledge is knowledge that we directly perceive to be true or false. That two is less than three or that nothing can be both all green and all red are known intuitively to be true. There is no need for a proof of intuitive claims; indeed, proofs cannot always be given because the truth is so certain. The next kind of knowledge is demonstrative knowledge, that is, knowledge that requires explicit proof. This kind of knowledge is only as certain as each step of the proof that is given. Still, it is typically not as certain as intuitive knowledge.

Locke takes a moment after the explanation of the different kinds and degrees of knowledge to address a skeptical worry. Since all knowledge is just the relations between ideas, how are we to know that the ideas we typically have are ideas deriving from experience and not ideas derived from memory or dreams. How is it that we can know we are not dreaming? In response to this concern, Locke describes his third degree of knowledge, sensitive. Sensitive knowledge is knowledge that, like our knowledge of pleasure and pain, comes from direct sensation.

Given these four forms of knowledge and three degrees of certainty, Locke can use all of the previous distinctions from his explanation to distinguish between different forms of knowledge. Since all knowledge is and can only be about and derived from ideas, all the different forms of ideas will also have their analogues in forms and modes of knowledge. Locke explains different variations of forms of knowledge and different degrees of knowledge. Knowledge derives from experience and ideas that are generated from experience are taken to be representational, that is, they represent the things that generate them. This helps us have certainty that at least some of our ideas represent what is going on in the external world. Locke, as we see above, is sensitive to the skeptical worry that there is no external world or that we are really just dreaming. However, his theory, given its empiricist and representational character, is more open to this skeptical attack than he may be aware.

After going through the different forms of knowledge, Locke then moves his analysis to truth. Here, Locke claims that truth cannot mean anything other than the agreement or disagreement of signs with one and other. Truth is, as he says, a property of propositions. Propositions are strings of signs or ideas. Typically they have the form of sentences, at least in their verbal form. These verbal or word propositions reflect mental propositions of ideas. There are, however, two other types of truth that Locke thinks are somewhat different from the formal notion of truth deployed here. The first is moral truth, which he cryptically describes as truth which is persuasive to our minds but that may or may not accord to the reality of things. There is also another kind of truth, metaphysical truth, which refers to the real essence of things.

Locke then goes on to discuss how we have knowledge of our own existence. He claims that we have intuitive knowledge of our own existence based on the individuation of our sensations. To feel pain, I must feel pain, hence there must be an I. Ultimately, Locke believes that the existence of the self is incapable of and does not really need proof. Still, he thinks that our knowledge of our own existence is certain and intuitive. Almost as certain for Locke is our knowledge of God. This is a tricky argument, as Locke cannot rely on any innate or other ideas not derived from experience to prove the existence of God. The proof is that there must be a real being that was the source of all other beings and that being must be a thinking being because no unthinking thing can create a thinking thing. Therefore we have certain, intuitive knowledge of God that is ultimately derived from experience.

Locke then goes on to argue that we have knowledge of other things through experience in the same way that we have knowledge of differences, that is, through our senses. He then goes on to discuss approximate types of knowledge including judgment and probability. Judgment is the ability to assent to ideas or propositions without certain knowledge, a kind of intuitive leap. Probability is the appearance of agreement without intuitive proof. After discussing reason and its basis, Locke goes on to discuss the difference between reason and faith. Locke argues that faith requires revelation and revelation also necessarily requires reasons. Reason must judge whether revelation deserves assent and hence there is no real distinction between faith and reason; faith must ultimately collapse into reason since even faith requires reason. Locke spends the final chapter discussing the proper division of the sciences. This division is based on his system of knowledge. He divides the sciences into natural philosophy, ethics, and the science signs. Natural philosophy, what would be metaphysics and natural science, is the study of bodies and their properties but since we only have secondary knowledge of these things, this branch of knowledge is, paradoxically, speculative. Ethics is the study of those things that tend to increase happiness and reduce pain. Finally, the science of signs analyzes our ideas directly and our words. Since, according to Locke, ideas and signs are really the base of all of our knowledge, this should be seen as the primary science.

This section contains 1,112 words
(approx. 3 pages at 400 words per page)
Copyrights
BookRags
An Essay Concerning Human Understanding from BookRags. (c)2016 BookRags, Inc. All rights reserved.
Follow Us on Facebook