The defining principle of the Renaissance is usually identified as humanism. By humanism, historians mean a return among intellectuals, especially in Italy, to classical knowledge. This was understood at the time as a rejection of the medieval scholasticism associated with such philosophers as Thomas Aquinas. Humanists studied ancient Greek, Roman, and Hellenistic texts in the belief that the classical wisdom they contained had something to offer in their own time. But for many writers and intellectuals like Petrarch, the seminal Italian poet whose works are often seen as foundation to the Italian Renaissance, humanism meant something more. It meant focusing on the secular as well as the divine. In his essay "Oration on the Dignity of Man," Pico Della Mirandola extolled the divine nature of man:
Imagine! The great generosity of God! The happiness of man! To man it is allowed to be whatever he chooses to be!
This new secularism, derived from humanism, was another of the defining principles of the Renaissance. For Machiavelli, it meant divorcing politics from religious or even moral principles, as he did most famously in The Prince. For a whole bevy of artists like Leonardo da Vinci, Raphael, Michelangelo, and many others, secularism meant portraying the human form in all its natural (albeit usually idealized) beauty. These new artists also embraced another principle important to the Renaissance--individualism. If people were divine, and one's humanity was not something to be ashamed of, then striving for individual greatness was a valid goal. Renaissance-era artists became something like celebrities, competing publicly with each other for patronage and fame. They sought to glorify God with their works, many of which were strongly religious in theme, but they also sought to glorify themselves.