ABSTRACT
In the thirteenth century the scope of philosophy was quite broad, encompassing everything that can be known about the universe by the use of reason alone, unaided by any special revelation.7 Theology or sacred doctrine (sacra doctrina), thus fell outside the remit of philosophy, and so did practical disciplines such as grammar, mechanics and medicine. Ethics, then as now, pertained to philosophical discourse, as did logic, natural philosophy and metaphysics, thereby reflecting a common division of philosophy that had come down to the Middle Ages from antiquity. Epistemology, especially as it is practised in contemporary English-speaking philosophy, did not yet exist, although the speculative issues connected with the study of human knowledge, its limits and objects did interest many thinkers of the period. Psychology, the study of the rational soul, was regarded as a branch of natural philosophy, as were all the disciplines that are now viewed as the natural sciences: astronomy, cosmology, chemistry, physics and biology.8 Mathematics was seen as belonging to philosophy, broadly construed, even though there was little agreement on the manner in which mathematical reasoning was to be related to natural philosophy.9
