In Chapter 7, what idea from Samuel Johnson does Carr end the chapter with?

Carr ends Chapter 7 with a quote from Samuel Johnson in which Johnson says there are two kinds of knowledge: what we know ourselves, and what we know about where to find information about a topic. Carr says that our over-reliance on the Internet to find answers and information has eroded our ability to know subjects in depth for ourselves rather than just being able to look up bits of information on a given topic piecemeal.