The autograph of the Interior Castle is to be found in the convent of the Discalced Carmelite nuns of Seville. When the book was first written its author's intention was to divide it only into seven main sections, or "Mansions", and not to make any subdivision of these into chapters. But by the time the manuscript was completed she had changed her mind, and, utilizing her margins, she was able to subdivide each of the seven parts of the book as she thought best. The titles of these sub-divisions she wrote on a separate sheet and they have unfortunately been lost. During her own lifetime, however, the nuns of her Toledo convent made a copy of the book, including these titles, which me so Teresan in style that their authenticity cannot for a moment be doubted.8 From the note already referred to written by Gracián in Ribera's biography of St. Teresa we learn that the Interior Castle, on its completion, was submitted to the closest scrutiny by himself and a Dominican theologian, P. Yanguas, in the presence of the author. The picture which he draws of these sessions is a memorable one.
8 The titles are here given in the form in which they appear in the editio princeps, which is practically identical with that of the Toledo copy.