Conservation

One of the key notions used in Piaget’s account of cognitive development is that of conservation. This refers to the idea that some abstract quantities remain constant even when they undergo surface changes. As an illustration, consider conservation of liquid.

A child is shown a glass of juice, which is filled up to a certain point. The juice is then poured into another glass that is shorter but wider than the original one. As a result, the juice does not go as high in the second glass as it did in the first, and from the child’s perspective it is no longer in the same shape in the second glass as it was in the first. Nonetheless, the quantity of juice remains the same. In Piagetian ...