The Impossible Event (a) In the habituation trials, infants watched a drawbridge flip back and forth with nothing in its path until they grew bored. Then a box was placed behind the drawbridge and the infants were shown one of two events: In the possible event, the box kept the drawbridge from flipping all the way over; in the impossible event, it did not. (b) The graph shows the infants’ looking time during the habituation and the test trials. During the test trials, their interest was reawakened by the impossible event but not by the possible event (Baillargeon, Spelke, & Wasserman, 1985).