Children's comprehension of the universal quantifiers all and each was explored in a series of experiments using a picture selection task. The first experiment examined children's ability to restrict a quantifier to the noun phrase it modifies. The second and third experiments examined children's ability to associate collective, distributive, and exhaustive representations with sentences containing universal quantifiers. The collective representation corresponds to the "group" meaning (for All the flowers are in a vase all of the flowers are in the same (...) vase). The distributive representation implies a pairing (e.g., each flower paired with a vase for Each flower is in a vase). The exhaustive representation exhausts both sets (e.g., for The flowers are in the vases all the flowers are in vases and all the vases have flowers in them). Four- to 10-year-olds children had little difficulty restricting the quantifier all to the noun it modified in a task which required them to attend to the group feature of all. In contrast, only 9- and 10-year-olds were able to solve the task when the quantifier was each and the pictures showed entities in partial one-to-one correspondence. Children showed a preference for associating collective pictures with sentences containing all and distributive pictures with sentences containing each. The results suggest that between the ages of 5 and 10 years, children's semantic representations undergo less radical changes than others have proposed. Instead, developmental change may occur gradually as children acquire linguistic cues which map onto existing semantic representations. (shrink)

The paper has sought to show two things. One is that the apparent variety of Stalnaker and Lewis's counterexamples is misleading. Several of their examples are quite unsatisfactory because they depend on unguarded language behavior. There is in fact only one type of counterexample that is worth serious discussion, and that has the form of Barense's.For Barense's example, I try to show that it fails as a counterexample to transitivity because one of the premisses is false within the context of (...) the example. However, Barense's example is problematic for the Stalnaker-Lewis analysis, since their device for avoiding transitivity (rejecting the rule of conditional proof) does not in fact eliminate anomalous conclusions that can be drawn when both the premisses are taken as true.In sum, there appears to be no good reason to doubt thatif is transitive, that the antecedent of a conditional can be strengthened, and that the contrapositive can be inferred. And the rule of conditional proof does seem to capture a commonly accepted form of argument in support ofif-then statements. (shrink)