There has been strong recent interest in formal reasoning processes and argumentation in science, focused mainly on linguistic, syllogistic methods for justifying claims based on inductive, deductive and abductive thinking. This agenda has arisen out of concerns to identify the epistemic distinctiveness of science as a discipline with specific expectations about how knowledge claims are structured and disseminated. While acknowledging the value of this agenda, we consider that reasoning in science can be understood more broadly to include informal reasoning processes emerging from the practices of inquiry and not just focused on justifying knowledge outcomes arising from this inquiry. These accounts of informal reasoning arise from a range of theoretical perspectives, including cognitive perspectives dealing with intuition, perception, pre-conceptual insights, pattern completion, and thought experiments, and socio-cultural perspectives on tacit, associative reasoning, and reasoning through participation in model construction practices.
In this paper we draw on our analyses of a recent ARC Project, the 'Role of representation in learning science', that entailed video capture of classroom sequences focused on student production of representations to explore, clarify, and justify their understanding of scientific concepts, processes and claims. We argue that a) the informal reasoning processes demonstrated by students in this study are as central to school science purposes and practices as they are to knowledge generation in science itself, b) these representational challenges open up opportunities to reason in various ways, c) informal reasoning through representation construction involves distributed claims and backing of a different nature to those represented in formal linguistic syllogistic accounts of reasoning, and d) the current framing of argumentation in school science captures only part of the complex processes of science knowledge generation and validation. For us, reasoning in school science is best seen as a set of diverse processes situated in an emergent practice of engaging in inquiry and authentic problem-solving activity. Therefore we further claim that the kinds of reasoning, argumentation, and explanatory accounts generated in this practice, from our semiotic, pragmatist perspective, entail a complex mix of formal and informal processes and understandings.
In the paper we will explore further the necessary interplay between these formal and informal reasoning processes and their theoretical underpinnings, in order to justify a richer pedagogical perspective.