Lenski traced these differences back to the Reformation and the Catholic church's reaction to it. In Lenski's view, the Reformation encouraged intellectual autonomy among Protestants, in particular Anabaptists, Puritans, Pietists, Methodists, and Presbyterians. In the Middle Ages, there had been tendencies toward intellectual autonomy, as exemplified in men like Erasmus. But after the Reformation, the Catholic church leaders increasingly identified these tendencies with Protestantism and heresy and demanded that Catholics be obedient and faithful to ecclesiastical discipline. In Lenski's opinion, his study showed that these differences between Protestants and Catholics survived to the present day. As a consequence, "none of the predominantly and devoutly Catholic nations in the modern world can be classified as a "leading" industrial nation. Some Catholic nations - such as France, Italy, Argentina, Brazil, and Chile - are quite highly industrialized, but none of them are leaders in the technological and scientific fields, nor do they seem likely to become so. Recently some Brazilian Catholic social scientists compared their country's progress with that of the United States and concluded that the chief factor responsible for the differential rates of development is the religious heritage of the two nations."