Fleurbaey-Michel conjecture on equitable weak Paretian social welfare order

► Explicitly describes order on infinite utility streams honoring anonymity and weak Pareto. ► Characterizes domains of one period utilities for which it is possible to describe order. ► Not possible to describe order for domains of order type similar to the set of integers. ► Resolves conjecture by Fleurbaey & Michel (2003) on explicit description of such orders. ► Shows identical domain restrictions for description of order and existence of SWF.