What are we talking about when we talk about ‘iambic shortening’?

The aim of the present article is to offer a collection of the available data on IS, focusing especially on the most relevant aspects from a linguistic point of view. Since many theories and beliefs about IS circulating in the literature have never been properly proved by means of a thorough analysis of the attestations, in parallel with the description of the phenomenology of IS a discussion of some traditional assumptions is included, in order to show which of them should be considered still valid and which are to be discarded instead. An overall interpretation of the phenomenon will not be proposed, because, in the author’s view, a satisfactory description of data must be pursued before and without being influenced by any hypothesis on them.