Chemistry Reference
In-Depth Information
Chapter 14
Investigating the Meaning of the Ceteris
Paribus Clause in Chemistry
Jean-Pierre No¨l Llored
14.1
Introduction
Ceteris paribus
is a Latin phrase, translated as “holding other things constant” and
is usually rendered in English as “all other things being equal.” This condition is
essential for the predictive purpose of any scientific inquiry and remains, explicitly
or not, a prerequisite for the validity of most inferences by comparison between
cases. Scientists first assume that one or more factors are fixed with the view to
analyzing the influence of another factor “in isolation.” This isolation can be
temporal if the factors fixed under the
ceteris paribus
condition actually change
slowly
relative to
other influences. In this situation, they are considered to be
practically constant during the experiment. Scientists can also refer to a causal
isolation if the factors frozen under the
ceteris paribus
condition are not signifi-
cantly affected by the process under study. Following this line of enquiry, not only
do experimentalists have to decide if a factor is negligible or not, but they also have
to define a relevant domain of study - macroscopic, mesoscopic, microscopic or
nanoscopic, and ensure that the phenomenon remains stable enough in order to
investigate the behavior of the system by the instrumentation at hands. In brief,
scientists gradually identify and stabilize the context from which a comparison
between cases paves the way for relevant inferences within a problem-solving
process.
Scientific conclusions must abide by this condition of comparison. In this
respect, the
ceteris paribus
condition is normative and is closely related to the
possibility of acceptable inferences from the special circumstances actually
