Ockham'S Razor

Historical Background

At the beginning of the 13th century, two new spiritual movements arose within a very short period of two decades and grew to a powerful position in medieval society: the so-called mendicant friars of the Franciscan and Dominican orders. The key elements of the Dominican calling were preaching to Christians and heretics alike and most important, converting all who were considered “heathens” (i.e., people of Jewish, Muslim, or nonorthodox Christian faiths) and establishing the knowledge, background, and learning to be able to do so. Therefore, Dominicans pressed into the newly founded universities in Paris, Oxford, and Cambridge to install a pertinent training, teaching, and research base for their enterprise. They were soon followed by the Franciscan friars. Although learning and academic work had not been a primary aspect of early Franciscan spirituality, Franciscans, too, soon understood that the Franciscan order also had to train its new members well if they were to complete their mission of reinvigorating Christian life and service to the community. Thus, the academic life and debates in the 13th century were largely dominated by these new movements and their academic beacons at the universities. One major challenge for these academics was to integrate Aristotelian science and philosophy into the traditional Christian teaching. Knowledge about Aristotle's philosophy had been scarce and based on only a few writings known to the West. Through both peaceful contacts with Islamic science, mainly in Spain and Sicily, and the combats surrounding the Crusades, such as the crusaders' sacking of Constantinople, more Aristotelian writings came to the West, and as a consequence, Aristotelian teaching became known. Thomas Aquinas (1225–1274), the mastermind of the Dominican order at that time, clearly saw that only a Christian reinterpretation of Aristotle would save a coherent picture of the world and give enough rational appeal to Christian theology, both for the satisfaction of critical Christian thinkers and philosophers and for armament against the Muslim theologians who had already integrated Aristotle into their worldview. Thus, Thomas Aquinas devoted his academic career to interpreting and amendingAristotle and reconciling him with Christian teachings. Part of this enterprise was the adoption of Aristotle's theory of perception and mental activity as expounded in his book De Anima [On the Soul]. The theory, briefly, supposes that in visual perception, for instance, the eyes extract what in Latin was called a species sensibilis, a perceptual template, if we may interpret freely.

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