In order to develop a theory of mind, a child must first develop intentional reasoning.
Intentional reasoning is a rudimentary understanding that people's intentions are different to our own.
Meltzoff provided evidence to show that 18 month have some understanding of other people's intentions.
Children observed adults putting beads into a jar. In the experimental condition, adults appeared to struggle to do this, whereas in the control condition they place beads in the jar successfully.
Results show that in both conditions the toddlers placed beads in the jar and the children in the experimental condition dropped no more beads than in the control condition.
While it shows that toddlers have some understanding of someone else's mental state and their intention, infants show no understanding of how others experience the world, and therefore don't yet have a real theory of mind.