2.2 Words: meanings

Categories and instances

There are lots of regularities in the world, properties that tend to go together or not to go together, events that tend to happen or fail to happen. Like other animals with powerful sensory systems built into our bodies and nervous systems, we can detect these regularities and use them to guide our behavior. We know what to expect when we drop something, when we bite into a potato chip, when we hear thunder.

Many of these regularities concern what we normally think of as objects. An object tends to cohere, to hold together even when it is pushed or pulled, to keep its weight, size, color, and texture. If the object is a living thing, it has properties that we can think of as abilities that are also relatively stable. If it can produce a certain kind of sound or walk in a particular way today, it normally can tomorrow too.

A further kind of regularity also concerns objects. The properties of objects tend to go together in clusters. The taste and smell of an apple go with the properties that define the appearance and the feel of an apple. The characteristic shape and size of a horse go with the characteristic gaits of a horse. These clusters of properties represent object categories. Each category, such as apple or horse, can described in terms of the set of properties that tend to belong to a particular cluster.

Note how a category is different from a particular object. A particular apple is an instance of the category apple because it has the characteristic properties of the category, but it also has some irrelevant properties of its own that make it unique. For example, it may be unusually small, sour, mushy, or shiny, or it may be bruised on one side. Instances of a category differ from each other in ways that are not relevant for the category.

There is much that we could say about categories, in fact much that is still not known about what they are and how we learn and deal with them. For now we need to emphasize one key point about categories, that they exist in the categorizing animal rather than in the world itself. We create categories as we learn about the regularities around us, and, importantly, we may not all create the same ones because we may notice and pick up on different sorts of regularities.

Categories and meaning

Where does language fit into all this? The words of a particular language amount to a kind of categorization of the world. The English word apple provides a kind of pointer to the set of properties that make up the category apple. We could think of this category, the meaning of the word apple, as something that exists within the English language (and many people treat meaning this way), but for the purposes of this course, we'll instead be emphasizing the fact that this category exists in the minds of speakers of English. The important point for now is that languages provide different categorizations of the world. There is not single Japanese word, for example, that corresponds exactly to the English word tree in meaning. The closest Japanese word, ki, encompasses many more objects in its meaning, including bushes and the wood that is derived from trees.

In this unit we'll look at the meanings of words that refer to categories of objects, that is, concrete nouns, and we'll do this first within a simple artificial language and artificial world within the MiniLing program.

Exercise 2.2

If you haven't already, download the version of the program to be used for this unit:

Download MiniLing: Words


Start up the program (which will be called "MiniLingWords.jar"). You will see a window with the title "MiniLing: Words" at the top. The black panel that makes up most of this window is where objects will be displayed. The white panel at the bottom is for forms.

Click on the button that says "Show a random object" and you should see the object in the meaning panel and the form of a word that refers to it in the form panel. The form will appear in characters that are unfamiliar to you. You don't have to worry about how these characters are pronounced (or even if they have pronunciations); all that matters is that the form for each word is a different sequence of characters. This button will only create objects that have names (words) in the language.

The language that is built into this version of the program has only seven words. To see the forms for these words, click on the button that says "Show all word forms". The forms will appear in a new window. Each of the words refers to a different category of objects. You can see an instance a particular meaning category by clicking on one of the word forms.

Observe several instances of each of the categories, either by clicking on the "Show a random object" button or selecting the word forms. For each of the word forms, describe as precisely as you can what the meaning of the word is.