Several studies of causal processing carried out on infants have taken as their model Michotte's (1963) research with adult subjects. Michotte presented visual stimuli involving what appeared to be two rectangles, A and B. A moved towards B at constant speed and came into contact with it, whereupon A remained at the point of contact and B moved off in the same direction at constant speed. Adult observers of this usually report that the movement of B is caused by the impact of A upon it, and that A pushes, kicks, or launches B. This is known in English as the 'launching effect'. Michotte reported that the effect was perceived by almost all observers, but he used trained observers who were familiar with the stimuli in most of his studies. Subsequent research has confirmed that many, though not all, adult subjects perceive the launching effect on their first exposure to the stimulus sequence (Boyle 1960; Beasley 1968; White 1988a). Considering that the stimuli were in all cases very imperfect representations of actual mechanical causality (Kassin and Baron 1985), the surprising thing is not that causal perception was not universal but that it occurred at all.