First stage in the adaptation of schema, assimilation allows a child to make a general interpretation of its world. In the 'bus' example (see Organisation), once the bus schema is formed the toddler for a while calls similar vehicles buses. On being contradicted by his/her mum, and also on the basis of experience in coming across more and more types of vehicle, he/she realises that a lorry etc. isn't a bus. They begin to be more stimuli specific and use the bus schema only in relation to buses. This is accommodation, or the second stage in the adaptation of schema.