•Why it earns a slot
Why it earns a slot: it is the book that invented childhood as its own stage of life rather than a defective draft of adulthood, and its Savoyard Vicar chapter got the whole work condemned and burned in Paris and Geneva within weeks of publication.
Rousseau spends five books arguing that the fastest way to ruin a child is to start teaching him too soon.
This distillation is written from the freely available original, which is always the better read when you have the time: Project Gutenberg.