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Asia-Pacific Forum
on Science Learning and Teaching, Volume 10, Issue 1, Article 3
(June, 2009) |
From novice to expert – ‘killing the metaphors’?
Goodwin (1994; 1995) has shown that deictic expressions are used to a high degree by professionals. In our data, deictic expressions are used approximately to the same degree by the different groups (see Figure 2). This may be connected to the presence of the visualizations in the interviews, which makes it easier to refer to an object or process by a deictic expression than by using the standard scientific terminology. The results indicate that the third year upper secondary students were able to retain a functional, process-related understanding of the content they studied one year before. Although, they found it at times harder to remember and use the proper domain-specific expression for the phenomena. By using the visualization and metaphors (which both probably also acted as a support for memory), and deictic expressions, the students were often able to give a satisfactory description in general accordance with the scientific understanding of the phenomenon, taking, of course, the learners’ level of education into account. However, the use of spontaneous metaphors and metaphors from teaching were lower at higher levels, and the results indicate a decrease in use of these kinds of metaphors, while the use of domain-specific expressions, among them many ‘dead’ metaphors, increases with higher levels of education (see Figure 2). The novice or learner moves away from spontaneous metaphors and metaphors used in teaching toward domain-specific terms when gaining in proficiency or competence. Experts can, however, return to the metaphors, relaxing the domain-specific terminology, in order to facilitate communication among themselves or when communicating with non-experts, but using the metaphors with a much more extensive depth of intention than the novice.
The language used in science textbooks is necessarily general and (at least ideally) precise. This general and precise terminology may however cause problems for students, whose interpretation of the terms are more vague and specific. It is more difficult for a novice to grasp in which way a term is precise (conceptually well-defined and delimited), at the same time as it is general (not limited to specific contexts). The precise terms and dead metaphors used in scientific language may be given unwanted connotations to everyday meaning by learners, thus causing difficulties in communicating the meaning between the teacher and the students. The teacher and students may therefore be talking past one another; the students not grasping the precise meaning and the teacher not fully recognizing the lack of precision in the students’ use of the scientific terminology. The abundance of students’ alternative conceptions discovered by science education research (Duit, 2008) is to a large degree connected to the problems of communicating the preciseness of scientific terms.
It is hard for a novice to go straight from a vague and general to a general and precise meaning of a term. One way of achieving this is to start the learning process by using the term in specific contexts and showing the learners how it can be used. In the case of molecular life science, visualizations such as those used in this study may be one way of specifying abstract and general concepts. An animation showing how DNA is unspecifically broken by UV radiation and specifically cut by a restricion enzyme might be one way of specifying, and, through more experience, making the meaning of break and cut in molecular life science more precise. The aim is to enable the learner to make a U-shaped turn in the model presented in Figure 1, starting in the upper left corner with an everyday, general and vague, meaning of break and cut ; being given a specific example; precifying the meaning of break and cut in this specific example; and finally reaching a precise and general meaning of break and cut through generalization of the use of these terms in several different situations.
In conclusion, this study has shown the importance for educators to take into account the difference in depth of intention between different individuals while using the same term. To use a scientific term is not necessarily equivalent to using it with a more extensive depth of intention. Furthermore, it supports the idea that it is of high value in educational contexts to be explicit about the range of meaning of a certain term or metaphor, and to be clear about what makes a domain-specific term precise instead of vague.
