As stated in the previous section, psychological researchers must carefully define their concepts. Some concepts are defined subjectively but, as you will see in this section and the next, for research purposes it is best to define concepts objectively.

In everyday life, people typically define concepts in an intuitive manner that is strongly influenced by personal biases, preferences, attitudes, etc. A subjective definition involves defining a concept in an intuitive manner based on general impressions — impressions influenced not only by reality but also by how one interprets reality (which allows personal biases, attitudes, etc., to affect one's observations). For example, Potter Stewart, an Associate Justice of the United States Supreme Court from 1958-1981, provided a subjective definition of obscenity (pronography) in a 1964 ruling. The case involved a French film, Les Amants (The Lovers), which had been banned from being shown in Ohio theaters because of an obscenity law in effect in that state. Nico Jacobellis, a manager of a theater outside of Cleveland, decided to show the film anyways. He was arrested and convicted. His case eventually made it to the Supreme Court, which ruled that the law had been incorrectly and unconstitutionally applied to the film. In his contribution to the majority decision, Stewart stated:

I have reached the conclusion ... that under the First and Fourteenth Amendments[,] criminal laws in this area are constitutionally limited to hard-core pornography. I shall not today attempt further to define the kinds of material I understand to be embraced within that shorthand description; and perhaps I could never succeed in intelligibly doing so. But I know [hard-core pornography] when I see it, and the motion picture involved in this case is not that. (JACOBELLIS v. OHIO, 378 U.S. 184, 1964; emphasis added)

Stewart admitted in his decision that he was defining the concept of "hard-core pornography" in an impressionistic and subjective manner; but his statement also seemed to imply that most people probably have the same subjective understanding of pornography as he, and that most therefore would agree with him when evaluating specific examples, just as we all can agree on which objects are red without being able to define precisely and objectively what "red" is. On this point, however, Stewart very likely was wrong: our standards of conduct and our moral values, which differ widely among individuals, determine whether or not we think something is "obscene." Stewart himself eventually realized this and changed his mind on the matter.

Subjective definitions and suggestion. The more subjective the definition of a concept is, the greater becomes the influence of "suggestion" on our observations. Suggestion is the automatic acceptance of an idea by an individual, who then acts on the idea with little or no critical reflection. In other words, what people say to you (or what they simply imply by their actions) can influence how you interpret your experience of an event or situation, and thereby, what you do in response to it. In most cases, this influence occurs without any awareness: that is, it occurs at either the preconscious or unconscious levels. In general, suggestion affects what we believe about an event or situation, and our beliefs about the event or situation influence what we perceive in it — that is, what sensory information we become conscious of.

A famous scientific example of the influence of suggestion on observations occurred at the beginning of the twentieth century. In 1903, soon after the discovery of X-rays — a previously unknown type of electromagnetic radiation that was invisible to the human eye — an eminent French physicist by the name of René Blondlot discovered what he called "N-rays" (named after the University of Nancy, which was where he worked). According to Blondlot and his colleagues, N-rays affect the perceived brightness of objects. For example, Blondlot claimed that N-rays increase the perceived brightness of electric sparks. Research supported his claim that N-rays are emitted from the sun, flames, and other glowing objects. In addition, according to these findings, certain substances, such as the vitreous[∂] fluid within the eye, absorb N-rays and then emit them later. This meant that, after N-rays are beamed into people's eyes, they become better able to see in darkened rooms. Most of Blondlot's claims were supported by dozens of studies performed in various laboratories. Thus, it seemed certain to many physicists that Blondlot had found something very important.

Nevertheless, as you will learn in this course there are always skeptics, which is good. It is best that scientific claims not be accepted too easily: doubts about the claim must be expressed in order to make certain that weaknesses in the claim are uncovered and additional research is performed. In the case of N-rays, a number of physicists doubted the evidence presented for its existence. They doubted the evidence because they were unable to replicate these findings in their own laboratories. Furthermore, in explaining their failures to replicate, they pointed to a basic problem in the initial research: in all of these studies, the researchers judged by sight (that is, subjectively) whether or not the brightness of an object supposedly being bombarded with N-rays had increased. These skeptical physicists argued that the suggestion that N-rays were aimed at the object being observed affected the researchers' perception of the object's brightness.

How could we test the claim that suggestion affected the perceived brightness of objects in these studies? The only way to do this would be to use deception: we would need to make observers believe incorrectly that N-rays either were being beamed at an object when they were not or not being beamed at the object when they were, and then ask for their observations (see Table 1).

Table 1. The design of a study of the effects of suggestion on
observations made in an N-Ray experiment

If the presence or absence of N-rays is the primary influence on what observers perceive, then Cell A and Cell C will contain the greatest number of instances in which the observers stated that the object appeared brighter to them; and Cell B and Cell D will contain the greatest number of instances in which the observers stated that the brightness of the object didn't change. On the other hand, if suggestion is the primary influence on what observers perceive, then Cell A and Cell B will contain the greatest number of instances in which the observers stated that the object appeared brighter to them; and Cell C and Cell D will contain the greatest number of instances in which the observers stated that the brightness of the object didn't change.

An American physicist by the name of Robert Wood performed this study in Blondlot’s laboratory in 1904:

N-ray experiments had to be carried out in a darkened laboratory.... This gave Wood an opportunity to make several observations that proved Blondlot’s judgements of brightness changes were a function of his beliefs [suggestion], and not of the presence or absence of N-rays. In one experiment, Wood was to block an N-ray source by inserting a sheet of lead between the source and a card with luminous paint on it [Blondlot had "discovered" that N-rays could not penetrate lead].... Without telling Blondlot, Wood changed the experiment in one slight but vitally important way. He would indicate to Blondlot that the lead sheet was blocking the N-ray source when it really wasn’t, or vice versa.... [Wood found that if Blondlot] believed the screen was present (blocking N-rays), but it wasn’t, he reported the paint to be less luminous. If he was told the screen was not present (allowing N-rays to pass), but it really was, he reported the paint to be more luminous. (Hines, 2003, p. 10). CHECK PAGE NUMBER

Thus, it was the observers’ beliefs about what was happening, not what actually was happening, that was the primary influence on their judgements of brightness. Further manipulations performed by Wood, similar in form to this one, provided no evidence to support the existence of N-rays. Hence, Wood concluded that all the previous evidence that seemingly supported the existence of N-rays actually were contaminated by the effects of suggestion.

What is most interesting about this story is that Blondlot never gave up his belief in the existence of N-rays: “convinced until the end that N-rays were real, [Blondlot] pursued his research on the topic until his death in 1930” (Hines, 2003, p. 11). Personal experience — in Blondlot's case, his perceptions of an increase in the brightness of objects under certain conditions — is very compelling evidence for us, even when objectively defined observations provide clear evidence in support of a different conclusion. The tendency to continue to hold a belief once it has been accepted as likely to be true is called belief perseverance. Once people have developed a belief, they tend to reject any argument providing clear and sufficient evidence for rejecting the belief. We all hold such “delusional” beliefs, partly because we don’t always realize how we might have been led astray by inaccurate personal experiences. That is why there is no substitute for research that controls for common problems in our everyday observations of the world. When faced with evidence from such research — evidence that contradicts our personal experience — we must be prepared to question and, perhaps, reject our beliefs, regardless of how compelling the personal experience was. We will return to this issue several times in this textbook.

Study Questions for Section 2-3

1. In your own words, how would you define "subjective definition"?
2. What is an example of a subjectively defined concept from your everyday life?
3. What would be an example of a subjective definition of an individual's
   (a) amount of intelligence,
   (b) amount of hunger,
   (c) degree of interest in a visual stimulus,
   (d) level of sexual desire.
4. How would you define in your own words the concept of "suggestion"?
5. What is an example from your everyday life of an experience you had with suggestion?
6. How can a suggestion influence what you perceive?
7. In what way are subjective definitions and suggestion associated?
8. What did the evidence for the existence of N-rays consist of?
9. What was the main problem with this evidence; and how did the notion of "subjective definitions" enter into this?
10. How was the evidence supporting the existence of N-rays shown to be inadequate?
11. Have N-rays been proved not to exist? Why or why not? (The answer to this question was not provided above. If you are unsure of how to answer it, ask in class.)

Go to Quiz 2-3 questions

Go to Readings Section 2-4