Processing Conditional Perfection in Promises and Threats: The Role of Negation, Clause Order and Incentive.

The paper reports on two experiments that investigate whether polarity, clause order and incentive influence derivation of Conditional Perfection in two types of inducements (promises and threats). Both experiments are designed as inference tasks, additionally measuring reaction times to inferences. The paper shows that the derivation of Conditional Perfection is endorsed in both types of inducements. However, the negative consequent bias (i.e. higher rates of Conditional Perfection in conditionals with a negative consequent than in conditionals with an affirmative consequent) and the double negation effect (i.e. slowdown of reaction times to Conditional Perfection with a double negation in a consequent) hold for threats, but not for promises. The paper also reveals a parallel double negation effect (i.e. facilitation of Conditional Perfection in conditionals with negation in both clauses) in threats, but not in promises. Last but not least, the paper demonstrates that the effect of clause order and incentive on the derivation of Conditional Perfection is rather moderate. The paper supports the view that the derivation of Conditional Perfection is not effortful (Van Tiel and Schaeken in Cogn Sci 41:1119-1154, 2016) and has some indirect arguments for treating Conditional Perfection and scalar implicatures as separate phenomena.