Argument-based interventions in science education have largely been motivated by the perspective that students lack knowledge of argument. Recent studies, however, suggest that contextual factors influence students' argument quality. The authors hypothesize that a key limiting factor lies in students' abilities to recognize when to employ knowledge related to argumentative reasoning. Students hold knowledge that can remain inert if the context fails to trigger access. The article reports on two experiments exploring the influence of context on recognition of argumentative reasoning. Each experiment used performance on a categorization task as the dependent variable. The first experiment (E1) tested the effect of targeted cues on participants' identification of fallacious reasoning patterns. The second experiment (E2) examined the role of scenario context. E1 revealed a significant advantage in promoting detection of fallacious reasoning patterns when targeted cues were present. E2 suggests that the broad context of scenarios also influences reasoning patterns. These findings reveal that lack of knowledge of argument may not be the principal constraint on students' argument abilities. Rather, contextual details can have a significant influence on activation of knowledge bases that contribute to argumentative reasoning. Instructional implications are discussed.