  According to the Russellian conception of propositions, a proposition is a complex entity with a particular structure whose constituents are particulars and/or properties and/or   relations.[17]  Are propositions of this sort abstract objects? If all the particulars are concrete then perhaps propositions are concrete objects, even if properties and relations are abstract. For one may say that propositions are where and when the particulars which are their constituents are. But this sounds arbitrary. Why not say that propositions are where their constituent properties and relations are, that is, nowhere? In any case, that particulars (and even properties and relations) are concrete does not immediately settle the matter whether propositions in the sense of complexes of particulars and properties and/or relations are abstract objects. For what kind of complex entities are propositions? Sometimes they are considered to be ordered sets. If this is what propositions are, then the nominalist needs a satisfactory nominalistic account of ordered sets. If propositions are another kind of complex entity, then the nominalist about propositions must make sure that objects of that kind are concrete.