Child climbing a bookshelf, c 1977.
© Manchester Daily Express / Science & Society Picture Library
'This two-year old is learning to climb, using his father's bookshelf as a ladder. If he reaches the top safely, the book or knick-knack that has caught his childish fancy is his. If he falls, he has grasped the lesson that climbing can be dangerous. By such trial and error methods we learn the basic skills of life - a process by which, psychologists say, a child acquires no less than a third of his intellectual skills by the time he is six'.