Machiavelli was yearning to return to politics. One of Machiavelli's aims in writing The Prince was to gain the favor of Lorenzo de' Medici, the then-governor of Florence and the person to whom the book is dedicated; he sought to earn an advising post inside the Florentine administration. However, all these attempts were in vain. Machiavelli's other goal was to inform readers on how to maintain or acquire power. He believed that political knowledge was essential for leaders to succeed. Without it, they would be like "untrained animals," as he put it in the preface. Machiavelli wanted to enlighten his contemporaries about the dangers of ambition and the need to keep one's word in politics. He also urged them to consider the effects of their actions before taking any decisive step. Machiavelli wrote The Prince in 1513 or 1514. It was first published in 1532 by Vittorio Colonna with the latter part missing. The complete work was later issued by Bernardo di Sandrone in 1540. On June 18, 1512, Lorenzo de' Medici died at the age of 39. His death left a leadership vacuum in Florence that was quickly filled by various factions. Machiavelli chose this moment to publish The Prince. The book became a success and soon after gained recognition as a textbook on government practices. This inspired many politicians to seek advice from Machiavelli.