How did the ideas of humanism lead to the reformation?
"Humanism is a group of philosophies and ethical perspectives which emphasize the value and agency of human beings, individually and collectively, and generally prefers individual thought and evidence (rationalism, empiricism), over established doctrine or faith (fideism)."
from http://en.wikipedia.org/wiki/Humanism
After the invention and use of the printing press, more people learned to read and they could read the Bible for themselves, not needing it to always be interpreted by someone in the church. The emphasis became more on the individual person and his/her thought, not just on the doctrines of the Church.