Editing Ceteris paribus (section)

=== Alfred Marshall's characterization ===

The clause is used to consider the effect of some causes in isolation, by assuming that other influences are absent. [[Alfred Marshall]]  expressed the use of the clause as follows:
{{Quote|The element of time is a chief cause of those difficulties in economic investigations which make it necessary for man with his limited powers to go step by step; breaking up a complex question, studying one bit at a time, and at last combining his partial solutions into a more or less complete solution of the whole riddle. In breaking it up, he segregates those disturbing causes, whose wanderings happen to be inconvenient, for the time in a pound called Ceteris Paribus. The study of some group of tendencies is isolated by the assumption other things being equal: the existence of other tendencies is not denied, but their disturbing effect is neglected for a time. The more the issue is thus narrowed, the more exactly can it be handled: but also the less closely does it correspond to real life. I.e. The more we apply the rule of ceteris paribus the further we distance ourselves from reality, e.g. If hydrocarbon fuels are infinite then society is sustainable.

Each exact and firm handling of a narrow issue, however, helps towards treating broader issues, in which that narrow issue is contained, more exactly than would otherwise have been possible. With each step more things can be let out of the pound; exact discussions can be made less abstract, realistic discussions can be made less inexact than was possible at an earlier stage.<ref>''Principles of Economics'', Bk.V,Ch.V in paragraph V.V.10</ref>}}