Critical psychologists need more than data

These three readers are part of a new series of nine books of Essential Readings in developmental psychology. I shall refer to them as books one, two and three. The readings are intended to illustrate important methodological, empirical and theoretical issues, as well as the state of research and current approaches. They aim to be accessible to students with limited knowledge of psychology.

At between 330 and 370 pages long, with between 13 and 19 chapters each, they cover a lot of ground, bringing together a broad range of basic empirical data. Many of the chapters address issues of contemporary significance. They are accessible, insofar as the language and style are not overly formal, while introductions to each chapter flag key points.

The books will be a valuable resource for students. But there is quite a variation in the quality of writing and content of chapters. Book one is the weakest, although the chapters on parenting, friendships, bullying, extracurricular activities and gender differences offer an empirical base and thoughtful analysis. In book two, I find Jean Piaget as brilliant as ever, while Robert Siegler’s chapter, reminding us of just how much dynamic variation can be observed in an individual’s behaviour in a short period, is a welcome rest from assumptions of static performance.

Kim Plunkett, a leader in the description of the power of connectionist modelling, makes a useful contribution, as does Esther Thelen, whose application of dynamic systems to motor learning is surely but a precursor of its use in psychological development in general. Other valuable contributions include Mark Johnson et al on infant visual attention, Karen Wynn on early numerical knowledge, Andrew Meltzoff on the imitation of non-performed intended acts by 18-month olds, and Kevin Miller et al on the influence of context (the number-naming system involved) on the development of mathematical knowledge. In book three, there are 19 chapters, all required reading for students of infant development.

Despite all these valuable features, I have a sense of unease. A psychology book should help make a good psychologist. Good psychologists need a grounding in basic data and the three readers provide such a database. But a psychologist, like any scientist, also needs methodological and evaluative skills to be able critically to interrogate that data. Psychologists need to be able to spot underlying assumptions and the conceptual framework guiding decisions about design, procedure and interpretation of results. These three readers are far more successful in giving basic information than at helping develop critical skills.

Take the social development reader. Can one not reasonably presume that social development in a variety of cultures will be covered? This would allow us to see how the macro-ecology of the socioeconomic context impacts on and interacts with social psychological factors and prevents the relatively naive reader from being led into thinking that some cultures are more important than others. Context is critical and yet there is no serious attempt to place social development in a broader framework. It looks as if the implicit message is that Americans are the most important people to study to understand human social development. Americans constitute the focus of almost all the research described. The young readers may be unknowingly influenced. They should not be.

Take also the portrayal of arguments about the nature/nurture dichotomy. In book three, we are offered an articulate account of the nativist position by Elizabeth Spelke. But we are not offered a comparable insight into other positions, such as that of "weaker" nativists, such as Renee Baillargeon, or empiricists, such as Plunkett, or even Linda Smith who regards the dichotomy itself as less then useful because "innate" does not refer to any specific mechanisms for developmental change and thus cannot possibly help explain how and why any particular change emerges. There can be no justifiable claim to being representative in this most basic area.

Finally, take the question of whether the interpretation of the behaviour of infants is indexical of their knowledge. Influential views in developmental psychology, such as are described in book three (eg Wynn in chapter ten and Baillargeon in chapter 11), depend on the validity of the assumption that infants look longer at novel than familiar events because they prefer them, and that extent of looking is thus a measure of novelty, or surprise, for the observer.

In chapter 11, extra looking is taken to show that the infant had a belief concerning the event, based on knowledge of physical principles, and that, if this belief is violated, surprise follows, hence the longer looking time. In chapter ten, the assumption is that after seeing a number of objects and operations moving some, a "correct" event is shown or an "incorrect" one, concerning the number of items present. The infant is assumed to look longer at the novel - that is, the "wrong answer" - event.

The point is not that these experiments are invalid, but that the assumptions are just that, and students are unlikely to have the sophistication to be able to critique these assumptions. Students need to be assisted step by step, and here they are not provided with examples of how to question assumptions. There is plenty of evidence that infants in many circumstances actually prefer the familiar, not the novel, depending on the details of the situation under consideration.

But I am showing my own assumptions. These contributions have much of value and provide really useful banks of research reports. They do cover a lot of ground, and they are, in the main, accessible. Read them, but take nothing for granted, even if some of the authors do.

Keith Richardson is senior lecturer in education, Centre for Professional Development and Information, Whitefields Schools, London.