%A Paul Franceschi %T A Brief Introduction to N-universes %X I describe in this paper the basic elements of the n-universes, a methodological tool originally introduced in Franceschi (2001) in the context of the study of Goodman's paradox. As the n-universes can be used in wide-ranging applications, such as thought experiments, I describe them from an essentially pragmatic standpoint, i.e. by describing accurately the step-by-step process which leads to a given modelisation. %D 2007 %K n-universes, thought experiment, time, space, Occam's razor %L cogprints5511