Helen Keller book The Story of My Life
Part III, Ch. 2: Personality http://books.google.com/books?id=zev1dMhB7C4C&q=Toleration+&quot;is+the+greatest+gift+of+the+mind+it+requires+the+same+effort+of+the+brain+that+it+takes+to+balance+oneself+on+a+bicycle&quot;&pg=PA295#v=onepage <br class="br">The Story of My Life (1903)