What did Einstein say about Piaget’s theory? How old was Piaget when he published an article on the sighting of an albino sparrow?

What did Einstein say about Piaget’s theory? How old was Piaget when he published an article on the sighting of an albino sparrow? What was Piaget’s interested area of study? Name two other psychologists who studied with Piaget. Which aspect of Piaget’s theory has been challenged by recent research?