  The similarity of these views to institutionalism is obvious, and the criticisms offered parallel those urged against institutionalism. First, historical definitions appear to require, but lack, any informative characterization of art traditions (art functions, artistic contexts, etc.) and hence any way of informatively distinguishing them (and likewise art functions, or artistic predecessors) from non-art traditions (non-art functions, non-artistic predecessors). Correlatively, non-Western art, or alien, autonomous art of any kind appears to pose a problem for historical views: any autonomous art tradition or artworks – terrestrial, extra-terrestrial, or merely possible – causally isolated from our art tradition, is either ruled out by the definition, which seems to be a reductio, or included, which concedes the existence of a supra-historical concept of art. So, too, there could be entities that for adventitious reasons are not correctly identified in historical narratives, although in actual fact they stand in relations to established artworks that make them correctly describable in narratives of the appropriate sort.  Historical definitions entail that such entities aren’t artworks, but it seems at least as  plausible to say that they are artworks that are not identified as such.  Second, historical definitions also require, but do not provide a satisfactory, informative account of the basis case – the first artworks, or ur-artworks, in the case of the intentional-historical definitions, or the first or central art-forms, in the case of historical functionalism.  Third, nominalistic historical definitions seem to face a version of the Euthyphro dilemma. For either such definitions include substantive characterizations of what it is to be an expert, or they don’t. If, on one hand, they include no characterization of what it is to be an expert, and hence no explanation as to why the list of experts contains the people it does, then they imply that what makes things artworks is inexplicable.  On the other hand, suppose such definitions provide a substantive account of what it is to be an expert, so that to be an expert is to possess some ability lacked by non-experts (taste, say) in virtue of the possession of which they are able to discern historical connections between established artworks and candidate artworks.  Then the definition’s claim to be interestingly historical is questionable, because it makes art status a function of whatever ability it is that permits experts to discern the art-making properties. 