Coercion effects, including aspectual ones, appear to indicate a modular grammatical architecture, in which the process of composition may add meanings absent in the syntax in order to ensure that certain functors, e.g., the progressive operator, receive suitable arguments (Herweg 1991, Jackendoff 1997, De Swart 1998). In this paper, coercion effects are instead taken as evidence for the existence of symbolic rules of morphosyntactic combination, which can, in cases of semantic conflict, shift the designations of lexical items with which they combine. On this account, enriched composition is a by-product of the ordinary referring behavior of constructions. Thus, for example, the constraint which requires semantic concord between the syntactic sisters in the string a bottle is also what underlies the coerced interpretation found in a beer. If this concord constraint is stated for a rule of morphosyntactic combination, we capture an important generalization: one combinatory mechanism underlies both coercion and instantiation. Since both type-selecting constructions (e.g., the French imperfective) and type-shifting constructions (e.g., the English progressive) require semantic concord between sisters, we account for the fact that constructions of both types perform coercion. Differences in the functional ranges of tense constructions in English and French are attributed to differences in coercion potential rather than differences in constructional semantics per se. Coercion effects are taken as evidence that aspectual sensitivity defines not only the French past tense, as described by De Swart (1998), but also tenses in general, including the English past and present tenses.