In Principles of Literary Criticism, I. A. Richards identifies two uses of language: referential (or scientific) and emotive. When we use language in a referential way, we point to a specific object that is a fact, a reality, something that can be verified as true or false. For instance, the referential or scientific way of speaking about one's heart refers to the physical organ that pumps blood through the body. On the other hand, emotive language is designed to appeal to emotions and attitudes, guiding a reader or listener to view an object through a particular lens that is not necessarily literally factual. Someone might say, for example, that when he received the news of a loved one's recovery from illness, his heart soared like an eagle with joy. Obviously, the person is not referring to his physical heart, which does not literally jump out of his body and fly through the air; rather, he is referring to an emotion and helping his listeners imagine the effects of that emotion for themselves.

The terms “statement” and “pseudo-statement” are related to the concepts of referential and emotive language. Referential language is made up of statements that point to something outside themselves and can be verified as a fact. For instance, the statement “The normal lung capacity of an adult male is about six liters” has been verified as true. Emotive language, especially poetic language, however, often uses pseudo-statements, statements that are not literally true but rather appeal to our emotions and attitudes and help us better understand our experiences. Someone who just ran a marathon, for example, might say something like, “My lungs are going to burst!” That is not literally true, of course. It is highly unlikely that bystanders will have to duck to dodge the runner's exploding lungs. But we can understand exactly what the speaker means because most of us have experienced the same feeling.

Richards uses the words “tenor” and “vehicle” to label the parts of one type of emotive language, the metaphor. A metaphor compares two objects (or persons or ideas), often one that is lessor known to the audience and one that the audience has more experience with. A tired parent with an energetic toddler might sigh and say, “Sally is a little jumping bean today.” Anyone who hears this statement, even without knowing Sally personally, has a good idea of what she is like. She hops and bounces from place to place just like a jumping bean. Using Richards' terminology, we would call Sally, the person described by the metaphor, the tenor and the jumping bean, the image used to describe Sally, the vehicle.

Finally, Richards often focuses on how readers respond to literary texts and why they respond in particular ways. He identifies stock responses as “views and emotions already fully prepared in the reader's mind” (Practical Criticism 240). These prepackaged or pre-programmed ideas that come from our previous education and past experiences affect how we respond to a text. Let's say that two students are reading a poem that mentions a garden. The student who has grown up in a large city would be most likely to picture a little vegetable garden in a vacant lot or even a window box filled with flowers, but the student who has grown up in a rural town would probably think of the huge vegetable garden in the back yard or the wide expanse of flowers surrounding the neighbor's house down the road. Further, the city student might think of a garden as something rather unique and exciting while the country student might regard a garden as beautiful and useful but also a lot of work. Each of these students, then, has a different stock response to the idea of a garden and will interpret the poem differently according to that response.