A child's ability to become deeply absorbed in something, and derive intense pleasure from that absorption, is something adults spend the rest of their lives trying to return to.

孩子能够全神贯注于某件事，并从中获得强烈的快乐，这是成年人终生都想要重新获得的一种能力。

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And part of the pleasure we derive from them is the knowledge that we could be reading something better.

NEWYORKER: Easy Writers