The book is a modest analysis of almost the totality of the letters sent by Martí to Gómez between 1877-1894, in it the feelings that impelled the Apostle to prepare what he called the "necessary war" are manifested. It gathers some of the Master's ideas present today in our philosophy of struggle, exemplified in the moment in which Martí considers that the Gómez-Maceo Plan lacked the necessary ingredient to make it viable, leaving latent that "among revolutionaries nothing can replace the bond of principles", then history would grant Martí the reason for his break with that project, which never constituted for him a renunciation to the struggle for independence, creating the premises later for a true revolutionary unity. It is addressed to lovers of history.