This post is the fourth part of "Critical Thinking and Mastery of Child Development Concepts".
Critical Thinking Problems Related to Topics in Developmental Science
In this section, I will describe some specific problems of critical thinking-- incidents where many thinkers make systematic errors-- and their relevance to some topics and problems of developmental science. It is possible that correction of these types of errors can help students understand material that they otherwise find confusing. It is also possible that the modeling of these errors by lecture or textbook may limit students' ability to detect them. The types of errors discussed here were chosen from a list put together by Gula (2002); the child development examples are my addition.
Problems of Irrelevance
A major critical thinking issue for most students is their inability to discriminate between relevant and irrelevant information, and their tendency to be distracted or confused by irrelevancies. I would point out again that our well-intentioned efforts to make textbooks and lectures vivid and engaging, through the use of vignettes and illustrations, add to the amount of irrelevant and distracting information presented to students.
The argumentum ad hominem. Forms of argument that focus on personal characteristics of theorists and researchers are appealing to students, but distract attention from the theory or research itself. Weaknesses of the individual or of his or her work are used as ways to evaluate entire systems. For example, a discussion of economics on National Public Radio recently began with some of the less attractive personal characteristics of John Maynard Keynes, and one discussant expressed surprise that the country was turning to such a person for solution of its economic difficulties. In discussions of developmental science, here are some similar situations, where an instructor might offer "gossip" as a way to get interest, and students might then reject the more important information: Piaget's observations of his own children are considered a reason to dismiss the entire theory of cognitive development; J.B. Watson's questionable treatment of little Albert, and his ill-judged advice about parenting, are seen as arguments against behaviorism; Kohlberg's suicide is taken to mean that his work on moral development is worthless.
The Appeal to Irrelevant Authority
Irrelevance can be confounded with other factors, too.
The appeal to the past. Arguments that begin with references to past claims ("Freud said...", "Parents have long known..."), without presenting further evidence, are distracting and conceal their irrelevance to the cognitive task at hand.
Apriority and the appeal to personal belief or experience: Students like to hear personal stories from their instructors, and publishers certainly believe that vivid personal details add to the desirability of a textbook. However, the use of such details presents two problems: first, the distraction of general irrelevancy, and second, the suggestion that if one individual's experience is of a certain kind, all or many others have similar experiences, and the vividly described experience can be taken as typical of an entire population. In fact, however, an individual's experience may be quite atypical and therefore irrelevant to population characteristics.
More generally, the appeal to personal experience involves the problem of apriority, or the building of argument on unexamined a priori assumptions of various kinds.
It is a common error of critical thinking to present speculation as if it is reliable evidence that backs up a claim ("confident speculation"). This error is an easy one to make in teaching about developmental science, as many claims are based on complex research whose details are far beyond what can be handled in a first undergraduate class. In addition, the many aspects of developmental work that are value-laden-for example, questions about physical punishment of children-may have little or no actual evidence basis.
Personal assurances of certainty. Especially when discussing emotionally-laden topics, instructors are often driven to say, "Nobody really knows, but I'll tell you what I think, for what it's worth." Students may attend much more carefully to the personal assurance given in this statement than to the warnings of possible uncertainty that the instructor feels he or she has given.
Appeal to personal experience. Because pedagogy for the last 40 years has stressed the need for students to make a personal connection with topics they are studying, most instructors and textbooks make a point of asking students to review their personal experiences. This was apparent in a number of the textbook quotations given earlier. In fact, however, the appeal to personal experience is a matter of confident speculation to the effect that the individual's experience is typical and representative of members of a group under study.
Developmental science, and development itself, are complex and multifactorial, and in many cases involve nonlinear relationships. Teaching and writing for undergraduates requires us to abstract and simplify some complicated material. The danger in terms of critical thinking is that necessary simplification will become oversimplification, and that we will fail to correct oversimplification by students.
The excluded middle, or categorical thinking. It is an error of critical thinking to assume, without evidence that phenomena belong to clearly dichotomous categories. This type of error is common in textbook statements and questions , but historically speaking, it is also a characteristic of the study of development, with its long discussion of a dichotomized Nature vs. Nurture. The love of typology is one of the more problematic aspects of the study of development. For example, note the many decades of acceptance of categories of attachment security (Ainsworth, Blehar, Waters, & Wall, 1978), and the minor interest displayed in attempts to examine attachment phenomena in terms of continuous variables (Roisman, Fraley, & Belsky, 2007).
The fallacy of the beard. This problem of critical thinking has to do with the understanding of overlapping categories. If a person has no whiskers, he doesn't have a beard; if he has hundreds of whiskers, he does have a beard. If he has two whiskers, or three, he has no beard, but the addition of more whiskers will eventually mean that there is a beard. Problems of this kind challenge critical thinking abilities because they require systematic discrimination of evidence and the recognition that definitions may be arbitrary. For the weak critical thinker, it is much easier to assume that if the phenomena overlap, there is no difference between them, or that, if the overlap is small, there are no similarities between them. The beard error is especially problematic for the understanding of gender differences and other population differences. Even more importantly for the teaching of developmental science, the fallacy of the beard interferes with the understanding of developmentally appropriate practice. Students prone to this fallacy may confuse the characteristics of toddlers, preschoolers, school-age children, and adolescents as they group all these ages under the rubric "children". Alternatively, and even alternately, they may exaggerate differences between adolescents and people of other ages, blurring the resemblances between adolescents and younger children.
Analogies and Metaphors
Analogies and metaphors are useful thinking techniques that compare two different things by showing the ways in which they are similar. These techniques are helpful in teaching about development, as many developmental events are difficult to observe directly or occur over long periods of time. The problem with analogies and metaphors is that although they may be used to convey ideas, they cannot in themselves establish an argument or support an inference. To attempt to use them in that way is to risk the error called "abusing an analogy." As Gula (2002) has suggested, analogies are abused when the terms of one element are used (and assumed) to predict the terms of another element.
Common analogies. Here are some common analogies and metaphors used in the teaching of developmental science: 1) "stages" or "milestones" of development; 2) the term "attachment" or "bond" to describe an attitude toward another person; 3) brain/cortical/ hand/ gene "dominance" (this metaphor may be one reason why it is so difficult for students to define dominant and recessive genes); 4) "regression" (not the statistical kind); 5) the term "sexual" in the description of psychosexual stages of development. These comparisons may be extremely valuable for teaching purposes, but their downside is the student's assumption that phenomena that have some things in common will have everything in common.
Easily abused analogies. In the study of development, one common instance of abuse of analogies involves reasoning from aspects of non-human development to aspects of human development. For example, John Bowlby's application of ethological concepts of imprinting in birds to human attachment abused an analogy, and was fortunately rejected after some consideration by developmental scientists. But this type of critical thinking error is still with us, and not in textbooks alone. For example, a recent article in the APA Monitor on Psychology (Price, 2009), entitled "Programmed for life?" has a subhead stating that "Your developmental environment can undercut your memory, give it a boost, or possibly even predict how you'll treat your children," but the reported study deals with factors influencing how much mice lick and groom their pups.
Affirming the Consequent and Other Forms of Transductive Reasoning
Piaget's discussion of preoperational cognition included a description of transductive reasoning, a form of primitive logic in which a child assumes that when two events share some characteristics, they are likely to share others, including a cause-and-effect relationship which may work in either direction. Piaget's famous example of this was a situation in which his daughter, given a cup of orange-colored chamomile tea, insisted that a green orange she wanted must have become ripe and attained the color that meant she could eat it. .
Affirming the consequent: This fallacy or error in critical thinking involves the practice of assuming that the converse, or reverse order, of a claimed condition is true. For example, let's take the statement that:
If a child has Reactive Attachment Disorder, she has lived in an orphanage or under similar conditions. [this is true, as the DSM list of criteria for the RAD diagnosis includes the etiology.]
The converse of this statement is the following:
If a child has lived in an orphanage (or under similar conditions), she has Reactive Attachment Disorder. [this claim is available to students on a number of Internet sites.] To assume that this converse statement is true without requiring other evidence is to affirm the consequent.
Denying the antecedent. This critical thinking error involves the assumption that if a positively-stated claim is true, a negative statement (the obverse) can also be assumed to be true, without further evidence. For an example, here is a common (although questionable) claim:
If a toddler carries a blanket around, it means he feels insecure without it.
Here is the obverse of the claim:
A toddler does not feel insecure [without a blanket], if he does not carry a blanket around.