AbstractThere is a great deal of validity in the position outlined by Macnamara and Austin; however, their ideas are part of an historical tradition. For the past 60 years, there have been a number of individuals who have noted major inconsistencies in Piagetian theory and/or significant problems with the methodology of the studies conducted within this framework. We welcome the addition of another voice to this chorus.We must know history in order not to be condemned to repeat it. George SantayanaThe only thing new in the world is the history you don't know. Harry TrumanIt was with a combination of surprise, delight, frustration, and anger that I read, Physics and Plasticine by Macnamara and Austin. As these are words that one does not typically find in a scientific journal, I shall explain why an article would engender such strong emotions. While I agree with the basic premises and conclusions of Macnamara and Austin (hence the delight), I feel that this article represents exceptionally poor scholarship (hence the surprise and the anger). In various ways, most of what Macnamara and Austin have written has been noted before and they seem to have ignored the challenges to the Piagetian system that have been made over the past 60 years and reviewed, for example, in Brainerd (1978a,b), Donovan and McIntyre (1990), Siegel (1978), and Siegel and Hodkin (1982) among others (hence the frustration). These challenges to the Piagetian ideas over the past 60 years (see Siegel & Hodkin, 1982 for a detailed review), start, as far as I have been able to determine, with the famous anthropologist, Margaret Mead (1932), who was critical of Piaget's concept of animism and what she perceived as Piaget erroneously attributing animistic thinking to the young child.Macnamara and Austin claim that There is opposition [to Piagetian theory] but it is mainly addressed to matters of experimental design and of problems relating to the transition from one stage to the next. Macnamara and Austin are incorrect. The opposition to Piagetian approach was based both on the presence of logical fallacies within the Piagetian position and criticisms of the methodology. While it is true that we criticized the methodology used by Piaget and his supporters, we also demonstrated that there were the problems with the underlying assumptions of this theory. We showed that the some of the premises ofthe theory were fundamentally flawed and that because of logical errors in their reasoning, the conclusions reached by the Piagetians were simply wrong. I will address some of these issues in this article.Faulty Logic: Language vs ThoughtThere has been criticism of the underlying logic of the Piagetian position (e.g., Siegel, 1978, 1982a). The Piagetian position is that cognitive operations emerge and develop independently of language. But the Piagetians rely on the child's verbal justifications and explanations to infer the existence of a particular cognitive structure. This use of language to measure thought is one of the fundamental problems with the theory because language is required to measure the cognitive operations that are supposed to exist without language. It is a paradox to rely on language to infer the existence or the nonexistence of a particular cognitive structure. In addition, there is ample evidence that preschool children, and in some cases even older children, do not understand the terminology of the questions used in Piagetian tasks or misunderstand or misinterpret the meaning of the question (e.g., Baron, Lawson, & Siegel, 1975; Lawson, Baron, & Siegel, 1974; Siegel, 1971a,b; Siegel 1977; Siegel, 1982a; Siegel & Goldstein, 1969). Therefore, if language is necessary to the measurement of a cognitive operation, the absence of such an operation cannot logically be inferred in a child ... whose language production and comprehension is immature and inadequate for the task. For such a child, the existence of a preoperational stage becomes at best, indeterminate. …