Candy and Deon begin this episode by discussing a recent email exchange between Jonathan Kominsky and Martin Packer about whether studies that use puppets are really testing young children's theory of mind rather than, for example, their "theory of puppets." Spoiler: Candy is less optimistic that they are; Deon is much more optimistic that, at the very least, they are approaching the question in the right way .
Candy and Deon then discuss a seminal paper by Wynn (1992) that examined 5-month-olds' capacity to add and subtract small numbers. Specifically, they discuss whether the claim "that infants are able to compute the precise results of simple additions and subtractions" (Wynn, 1992, p. 749) is supported by the data. Candy and Deon discuss why they think that the claim is not supported by the data and then go on to discuss some mixed evidence for this claim from follow-up replication attempts.
Cohen, L.B., & Marks, K.S. (2002). How infants process addition and subtraction events. Developmental Science, 5(2), 186-201. Link to paper
Simon, T.J., Hespos, S.J., & Rochat, P. (1995). Do Infants Understand Simple Arithmetic? A Replication of Wynn (1992). Cognitive Development, 10, 253-269. Link to paper
Wynn, K. (1992). Addition and subtraction by human infants. Nature. 358, 749-750. Link to paper