We develop a model of undescribable events. Examples of events that are well understood by economic agents but are prohibitively difficult to describe in advance abound in real life. This notion has also pervaded a substantial amount of economic literature. Undescribable events in our model are...

We develop a model of unforeseen contingencies. These are contingencies that are understood by economic agents — their consequences and probabilities are known — but are such that every description of such events necessarily leaves out relevant features that have a non-negligible impact on...