All the same,’ said the Scarecrow, ‘I shall ask for brains instead of a heart; for a fool would now know what to do with a heart if he had one.
-- Scarecrow (Chapter 5 paragraph 52)

Importance: From the beginning, the Scarecrow discusses his desire for brains. It's evident to the reader from early in the book that the Scarecrow is beginning to learn and that his desire for brains is his way of hurrying the learning process. This quote is part of the conversation between the Scarecrow and the Tin Woodman soon after their meeting.

I shall take the heart,’ returned the Tin Woodman; ‘for brains do not make one happy and happiness is the best thing in the word.
-- Tin Woodman (Chapter 5 paragraph 53)

Importance: This line follows the Scarecrow's declaration that he would prefer to have a brain rather than a heart. The Tin Woodman believes he could become happy if he had a heart because he believes the...