Some facts one simply cannot deny

Two-, three-, and four-year-old children were tested on a variation of Wason's (1965) procedure for testing the effects of plausibility on the comprehension of negative statements. It was found that negatives about an exceptional item in an array, i.e. plausible negatives, were understood before implausible negatives. Reaction time data revealed that plausible negatives were also processed more rapidly for three- and four-year-olds. An additional effect on plausibility, namely the degree of confusability between the different items in an array, was proposed, and was found to become increasingly salient with age.