Computational reproducibility possesses its own dynamics and narratives of crisis. Alongside the difficulties of computing as an ubiquitous yet complex scientific activity, computational reproducibility suffers from a naive expectancy of total reproducibility and a moral imperative to embrace the principles of free software as a non-negotiable epistemic virtue. We argue that the epistemic issues at stake in actual practices of computational reproducibility are best unveiled by focusing on software as a pivotal concept, one that is surprisingly often overlooked in accounts (...) of reproducibility issues. Software is not only about designing and coding but also about maintaining, supporting, distributing, licensing, and governance; it is not only about developers but also about users. We focus on openness debates among computational chemists involved in molecular modeling software packages as empirical grounding for our argument. We then identify and analyse four epistemic characteristics as key to the role of software in computational reproducibility. (shrink)

A new chronology is introduced to address the history of chemistry, with educational purposes, particularly for the end of the twentieth century and here identified as the fifth chemical revolution. Each revolution are considered in terms of the Kuhnian notion of ‘exemplar,’ rather than ‘paradigm.’ This approach enables the incorporation of instruments, as well as concepts and the rise of new subdisciplines into the revolutionary process and provides a more adequate representation of such periods of development and consolidation. The fifth (...) revolution developed from 1973 to 1999 and is characterized by a deep transformation in the very heart of chemistry. That is to say, the size and type of objects, the way in which they must be done and the time in which they are transformed. In one way or another, chemistry’ limits had been set out. (shrink)

A layered interpretation of the history of chemistry is discussed through chemical revolutions. A chemical revolution mainly by emplacement, instead of replacement, procedures were identified by: a radical reinterpretation of existing thought recognized by contemporaries themselves, which means the appearance of new concepts and the arrival of new theories; the use of new instruments changed the way in which its practitioners looked and worked in the world and through exemplars, new entities were discovered or incorporated; the opening of new subdisciplines, (...) which produced, separated scientific communities. The fourth chemical revolution, fundamentally characterized by the incorporation of new instruments in chemical practices is discussed. (shrink)