Abstract: This experiment studied the development of causal reasoning in 66 3.5- to 4.5-year-olds using a ramp apparatus with two input holes and two output holes (Frye et al., 1995). Results revealed that (1) children performed better on cause-effect inferences than on effect-cause inferences; (2) there was an effect of rule complexity such that uni-dimensional causal inferences were easier than bi-dimensional inferences which, in turn, were easier than tri-dimensional causal inferences; and (3) children’s causal reasoning develops rapidly between the ages of age of 3.5 to 4 years.

Key words: causal reasoning, rule dimensions, reasoning directions, cognitive development