Humanism is an educational and cultural philosophy that began in the Renaissance when scholars rediscovered Greek and Roman classical philosophy and has as its guiding principle the essential dignity of man. Humanism was the intellectual movement that informed the Renaissance, although the term itself was not used to describe this discovery of man until the early nineteenth century. Humanist thinking came about as a response to the scholasticism of the universities. The Schoolmen, or scholastics, valued Aristotelian logic, which they used in their complicated method of defending the scriptures through disputation of isolated statements. Humanists accused the scholastics of sophistry and of distorting the truth by arguing philosophical phrases taken out of context. By contrast, humanists researched the historical context and lives of classical writers and focused on the moral and ethical content of the texts. Along with this shift came the concept that "Man is the measure of all things" (Pythagoras), which meant that now Man was the center of the universe in place of God. In turn, the study of man and human acts on Earth led humanists to feel justified in entering into the affairs of the world, rather than leading a life of monastic asceticism, as did the scholastics.

The first humanist, Francesco Petrarch coined the term "learned piety" (docta pietas) to indicate that a philosopher may love God and learning, too. The common thread between all Renaissance humanists was a love of Latin language and of classical (Roman and Greek) philosophy. The humanist interest in authenticating classical texts would become the field of textual criticism that still thrives today. Humanism, too, thrives today, although it has been transformed to encompass humanitarian concerns such as providing aid to others who are suffering. Today's secular humanists actively reject religion and turn their attention to charitable works and an ethical, meaningful life on Earth.