The role of externalisation in reasoning with self-constructed representations

This paper explores some of the issues related to the difference between selecting, constructing and using one´s own external representations (ERs) versus using pre-fabricated ERs such as textbook diagrams. The focus is upon the role of externalising the representation during ER construction. Some of the issues addressed in this paper stem from a series of studies on how students reason with external representations (ERs) in a range of contexts. They include learning first-order logic using a computer-based graphical system and interpreting syllogisms presented sententially and graphically. In those two domains, subjects reasoned with pre-fabricated diagrammatic representations of information in the domain. Spontaneously produced, subject-constructed, work-scratching ERs have also been investigated in the domain of analytical reasoning. Analytical reasoning problems are constraint satisfaction puzzles similar to those found in the US Graduate Record Examination (GRE). An example is provided