Dienes & Perner (D&P) argue that nondeclarative knowledge can take multiple forms. We provide empirical support for this from two related lines of research about the development of mathematical reasoning. We then describe how different forms of procedural and declarative knowledge can be effectively modeled in Anderson's ACT-R theory, contrasting this computational approach with D&P's logical approach. The computational approach suggests that the commonly observed developmental progression from more implicit to more explicit knowledge can be viewed as a consequence of (...) accumulating and strengthening mental representations. (shrink)

Gesture does not have a fixed position in the Dienes & Perner framework. Its status depends on the way knowledge is expressed. Knowledge reflected in gesture can be fully implicit (neither factuality nor predication is explicit) if the goal is simply to move a pointing hand to a target. Knowledge reflected in gesture can be explicit (both factuality and predication are explicit) if the goal is to indicate an object. However, gesture is not restricted to these two extreme positions. When (...) gestures are unconscious accompaniments to speech and represent information that is distinct from speech, the knowledge they convey is factuality-implicit but predication-explicit. (shrink)