Before they were Illuminati, they were Perfectabilists.
"But in the 1500s, a group of men in Rome fought back against the church. Some of Italy's most enlightened men -- physicists, mathematicians, astronomers -- began meeting secretly to share their concerns about the church's inaccurate teachings. They feared that the church's monopoly on 'truth' threatened academic enlightenment around the world. They founded the world's first scientific think tank, calling themselves 'the enlightened ones.'"
"Yes," Langdon said. "Europe's most learned minds ... dedicated to the quest for scientific truth."