The modern emphasis in methodological naturalism primarily originated in the ideas of medieval scholastic thinkers during the Renaissance of the 12th century:
- By the late Middle Ages the search for natural causes had come to typify the work of Christiannatural philosophers. Although characteristically leaving the door open for the possibility of direct divine intervention, they frequently expressed contempt for contemporaries who invoked miracles rather than searching for natural explanations. The University of Paris cleric Jean Buridan (a. 1295-ca. 1358), described as "perhaps the most brilliant arts master of the Middle Ages," contrasted the philosopher's search for "appropriate natural causes" with the common folk's habit of attributing unusual astronomical phenomena to the supernatural. In the fourteenth century the natural philosopher Nicole Oresme (ca. 1320–82), who went on to become a Roman Catholic bishop, admonished that, in discussing various marvels of nature, "there is no reason to take recourse to the heavens, the last refuge of the weak, or demons, or to our glorious God as if He would produce these effects directly, more so than those effects whose causes we believe are well known to us."
- Enthusiasm for the naturalistic study of nature picked up in the sixteenth and seventeenth centuries as more and more Christians turned their attention to discovering the so-called secondary causes that God employed in operating the world. The Italian Catholic Galileo Galilei (1564–1642), one of the foremost promoters of the new philosophy, insisted that nature "never violates the terms of the laws imposed upon her."
[11] Ronald L. Numbers (2003). "Science without God: Natural Laws and Christian Beliefs." In: When Science and Christianity Meet, edited by David C. Lindberg, Ronald L. Numbers. Chicago: University Of Chicago Press, p. 267.