Jean-Jacques Rousseau, a prominent philosopher and educational thinker, was a strong advocate for child-centered education and the importance of fostering children's natural development. He believed that children should be allowed to explore and learn through their own experiences, rather than being subjected to rigid rules or external control. According to Rousseau, children have an innate goodness and should be given the freedom to develop at their own pace.
Answer: $\boxed{\text{The child's freedom}}$