“The energy of book titles and the words inside them are very powerful. In Japan, we say that ‘words make our reality.’ [言葉が現実をつくる] The words we see and with which we come into contact tend to bring about events of the same nature. In that sense, you will become the person that matches the books you have kept. What kind of books would you want in your bookcase to reflect the kind of person you aspire to be? If you choose which books to keep on that basis, you may find that the course of events in your life changes dramatically.”

— Marie Kondo (konmari), Spark Joy, page 130

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Spark Joy: An Illustrated Master Class on the Art of Organizing and Tidying Up