Excerpt: The papers that appear in this special issue bring together researchers working on probabilistic models of cognition with developmental psychologists, to consider how “rational constructivism” could shed light on some of the challenges of understanding cognitive development. Our goal in collecting these papers together is to illustrate that this new approach to the study of cognitive and language development has already shown a lot of promise – both computational modeling and empirical work have opened up new directions for research, and have contributed to theoretical and empirical advances in understanding learning and inference from infancy to adulthood. The rational constructivist view embodies two key ideas: one is the commitment that the learning mechanisms that best characterize learning and development from infants to adults are a set of rational, inferential, and statistical mechanisms that underlies probabilistic models of cognition. The application of these domain-general mechanisms may give rise to domain-specific knowledge. The second is to call into question both the nativist characterization of innate conceptual primitives (e.g., is object or agent an innate concept?), and the empiricist’s characterization of a newborn infant with nothing but perceptual primitives and associative learning mechanisms. It is an open question how best to think about the initial state of a human learner. Perhaps in addition to a set of perceptual (proto-conceptual?) primitives, the infant also has the capacity to represent variables, to track individuals, to form categories and higher-order units through statistical analyses, and maybe even the representational capacity for logical operators such as and/or/all/some – these capacities enable the infant to acquire more complex concepts and new learning biases. As such, this view departs from the traditional Piagetian view of development in at least two ways – development does not progress through stages, driven by qualitative changes in the child’s logical capacities, and development does not start with sensory-motor primitives and a lack of differentiation between the child and the world. Instead, the construction of new concepts and new learning biases is driven by rational inferential learning processes. At the moment, there is by no means any consensus on these issues. With further empirical and computational work, a more detailed explication will emerge.

The authors in this chapter focus on a case study of how object representations in infants interact with early word learning, particularly the nature of the so-called ‘shape bias’. A short review of the controversies in this subfield is used to illustrate the two dominant views of cognitive development, which can be roughly classified as nativist or empiricist. Also presented are theoretical arguments and new empirical evidence for a rational constructivist view of cognitive development. The authors’ goal in this chapter is to argue for a new approach to the study of cognitive development, one that is strongly committed to both innate concepts and representations, as well as powerful inductive learning mechanisms. In addition to discussing the ‘shape bias’ and how it relates to object representations, generality of the approach is briefly discussed.

Key words: object representations, early word learning, shape bias, cognitive development, nativist, empiricist, rational constructivist, innate concepts, inductive learning mechanisms, infants