What is science without replication?

Excerpt

The Latin adagio unus testis nullus testis is an important principle that equally applies to criminal law as to science: we should not base our conclusions on a single piece of evidence [1]. Of course, criminal law and science are very different practices. After all, while a criminal case typically revolves around the evaluation of evidence in favour of and against competing hypotheses about what occurred in a particular case with specific actors, the goal of science is to establish generally applicable laws and principles. Yet, what unites the two practices is that both are about establishing a chain of evidence: pieces of evidence have to be anchored as narratives into a story line that increases the plausibility of some hypothesis relative to competing hypotheses. Just like a DNA match from a cigarette found at a crime scene cannot be sufficient to conclude on the guilt of the suspect in the absence of contextual information on how the cigarette got there (e. g. eyewitness testimonies), the meaning of findings from a scientific study cannot be established without considering context, theory and relevant previous research. In other words, science too is about storytelling [2]. …