_Conjectures and Refutations_ is one of Karl Popper's most wide-ranging and popular works, notable not only for its acute insight into the way scientific knowledge grows, but also for applying those insights to politics and to history. It provides one of the clearest and most accessible statements of the fundamental idea that guided his work: not only our knowledge, but our aims and our standards, grow through an unending process of trial and error.

A crucial part of the knowledge of molecular biologists is procedural knowledge, that is, knowledge of how to do things in laboratories. Procedural knowledge of molecular biologists involves both perceptual-motor skills and cognitive skills. We discuss such skills required in performing the most commonly used molecular biology techniques, namely, Polymerase Chain Reaction and gel electrophoresis. We argue that procedural knowledge involved in performing these techniques is more than just knowing their protocols. Creative exploration and experience are essential for the acquisition (...) of procedural knowledge in molecular biology. With enough experience, molecular biologists make intuitive judgments without recourse to analytical reasoning. We propose that procedural knowledge is intuitive recognition of the patterns of one's environment that are the most relevant for making a decision or acting appropriately. Finally, we argue that knowledge of molecular biologists requires an integration of procedural knowledge and propositional knowledge. (shrink)

This paper presents a skill learning model CLARION. Different from existing models of mostly high-level skill learning that use a top-down approach (that is, turning declarative knowledge into procedural knowledge through practice), we adopt a bottom-up approach toward low-level skill learning, where procedural knowledge develops first and declarative knowledge develops later. Our model is formed by integrating connectionist, reinforcement, and symbolic learning methods to perform on-line reactive learning. It adopts a two-level dual-representation framework (Sun, 1995), with a combination of localist (...) and distributed representation. We compare the model with human data in a minefield navigation task, demonstrating some match between the model and human data in several respects. (shrink)

Learners are able to use 2 different types of knowledge to perform a skill. One type is a conscious mental model, and the other is based on memories of instances. The authors conducted 3 experiments that manipulated training conditions designed to affect the availability of 1 or both types of knowledge about an artificial grammar. Participants were tested for both speed and accuracy of their ability to generate letter sequences. Results indicate that model-based training leads to slow accurate responding. Memorybased (...) training leads to fast, less accurate responding and highest achievement when perfect accuracy was not required. Evidence supports participants’ preference for using the memory-based mode when exposed to both types of training. Finally, the accuracy contributed by model-based training declined over a retention interval. (shrink)

Complete URL to this document: http://srsc.ulb.ac.be/axcWWW/93-Principles.html.

Synthesizing situated cognition, reinforcement learning, and hybrid connectionist modeling, a generic cognitive architecture focused on situated involvement and interaction with the world is developed in this book. The architecture notably incorporates the distinction of implicit and explicit processes.