An Essay Concerning Human Understanding | Study Guide

John Locke

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An Essay Concerning Human Understanding | Vol. 2, Book 3, Chapters 10–11 : Of Words | Summary



Vol. 2, Book 3, Chapter 10: Of the Abuse of Words

Although language is naturally imperfect, Locke observes that people often compound the problem by "render[ing]" linguistic signs "less clear and distinct in their signification, than naturally they need to be." Language can be "abused" in numerous ways, including the use of "words without any, or without clear ideas." This happens when people learn the names of things without understanding the corresponding concepts. Other abuses of words include:

  • "Unsteady application," meaning inconsistency or self-contradictoriness in the way a word is used.
  • "Affected obscurity," or the introduction of "new and ambiguous terms" or the creation of new meanings for old words. Locke says this flaw is particularly common among academics, who often try to pass it off as a sign of intelligence.
  • "Taking [words] for things"—for Locke, it's important to remember that words represent our ideas of things, not the things themselves. Just because something can be named does not mean it exists.
  • "Setting [words] for what they cannot signify," or assuming that a word denotes the real essence of a thing. Since real essences are unknown, words cannot point to them.
  • "A supposition that words have a certain and evident signification"—when people assume their meaning is obvious to everyone, they often end up using the same word to mean different things.

Finally, Locke says, figurative speech can sometimes be an abuse of language. "In discourses where we seek rather pleasure and delight than information and improvement," Locke concedes, figurative speech is fine. But when "we would speak of things as they are," artificial eloquence can be misleading and hinder our quest for truth. Locke reminds the reader that the "end" (i.e., goal) of language is to convey ideas quickly and accurately. Anything that stands in the way of this goal is an abuse of words.

Vol. 2, Book 3, Chapter 11: Of the Remedies of the Foregoing Imperfections and Abuses

Fixing these errors and preventing these abuses, Locke remarks, is "not easy," but it is "necessary to philosophy." When words are misused, intentionally or otherwise, the result is "obstinacy" (dogmatic stubbornness) and "wrangling" (pointless, pedantic disputes). The "remedy," Locke says, is "to use no word without an idea," and to make sure that idea is a distinct one which—when applicable—conforms with outward reality. When a word's meaning is established by custom, that custom should be obeyed by default. When a meaning is apt to be unclear, its meaning needs to be made known, whether by demonstration, definition, or a mixture of the two. Lastly, Locke proposes, words should be used unambiguously. When a word must unavoidably be used in two different senses, those divergent meanings need to be explained.


Much as he did in Book 2, Locke ends Book 3 with a focus on what can go wrong. He is more optimistic about language, however, than he was about ideas. Broadly speaking, Locke construes language as something like a network of pipes that carry ideas among people. The pipes may be rusty, corroded, broken, or stopped up, but they're "out there" in the world where they can be examined and repaired. Ideas are hard to fix, even in principle, because they exist separately in each person's mind. Language, on the other hand, is constantly being brought out into the public forum.

Some of Locke's "abuses of language" seem relatively harmless, though they can easily derail a work—such as a philosophical treatise—which depends on precision. "Taking words for things" and "setting words for what they cannot signify" both point back to Locke's discussion of real and nominal essences (Chapter 6). The failure, in both cases, amounts to a failure to distinguish between words and the reality they reflect. Interestingly enough, Locke himself was accused of "affected obscurity" in his choice of words throughout the Essay. After his treatise was published, the Bishop of Worcester wrote Locke to complain that the term idea had come into vogue. People, he grumbled, were using this word to sound smart, when they meant "only common notions of things, which we must make use of in our reasoning." Compared with that clunky phrase, the word idea seems clear and succinct, but only because it's now been in use for centuries.

Other "abuses" have more obvious practical effects. One trick Locke despises is the tendency to use one word with two different meanings, which he here calls "unsteady application." This is different from mere punning or wordplay, which—as long as it occurs outside of "philosophical conversation"—Locke has no problem with. In other cases, like the infamous "ham sandwich fallacy," it's easy to tell that something is amiss, but it can be hard to articulate just what is wrong. The fallacy is formally but less colorfully known as the "fallacy of four terms." Deborah J. Bennett, author of Logic Made Easy (2005), states it as follows:

A ham sandwich is better than nothing.
Nothing is better than eternal happiness.
Therefore, a ham sandwich is better than eternal happiness.

The fallacy results from two different definitions of the word "nothing"—a lack of something vs. something incomparable. Thus, although the first and second sentences use the same word, they are not truly equivalent.

Locke's concern here is that philosophers, theologians, and other early modern thought leaders will indulge in such ham-sandwich reasoning, but much more subtly. They might start out with a simple and agreeable definition of "mind" or "matter," then end up proving propositions based on a quite different definition. If they do so purposely, they are frauds; if they do so accidentally, they are wasting people's time. These kinds of fallacies, as Locke acknowledges, can be difficult to spot. Worse yet, the formal tools of reasoning commonly taught in Locke's day are of little help in dealing with this kind of equivocation. Locke will have more to say about logic and its limits throughout Book 4, particularly in Chapters 7 and 17.

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