The Bristol Inquiry is arguably one of the most important cases of judicial medical investigation held in the United Kingdom (UK), which continues to raise important insights into the social construction of medical and scientific risks. As a way of marking the inquiry’s tenth anniversary year, this article returns to an important conversation held between noted pediatric cardiothoracic and cardiovascular specialists, on days 49 and 50 of the inquiry’s proceedings. Their conversance principally describes a pathway of scientific advancement across four decades (c. the mid-1960s to 1999). Risks, and the avoidance of medical error (iatrogenesis), represent important subtopics of the ensuing historical narrative, within which the experts describe opportunities for error as diminishing in-line with paradigmatic advancement. The telling of this story of risk mitigation involves the expurgation of considerable sensitivities to scientific uncertainty. In analyzing this example of expert scientific witness testimony, the article primarily considers how representations of uncertainty are formulated in language. The article concludes that, in this instance, the social construction of risk and uncertainty were heteroglossically premised upon language catalysts, cognitive metaphors, and logic-based mathematical rubrics.