This illustration pairs a codified version of the biblical T-O scheme with an Aristotelian scheme for geographic organization. Where the T-O scheme relies on Scripture to establish the frame of reference, the older Greek model is derived from motion in the “sphere of fixed stars,” which appeared to revolve around Polaris, the North Star. In the Aristotelian model, the hemisphere is viewed horizontally—a 90-degree shift from the top-down view of the Northern Hemisphere used in T-O maps.
In the ancient model, the Tropics (derived from the adjectival form of τροπικός, ‘to turn’) were also established astronomically. Their distance from the Equator corresponds to the distance between the Celestial Equator and the points to its North and South delineated by the apex of the Sun’s arc on the summer and winter Solstices. Their names—Cancer and Capricorn—come from the respective segments of the zodiac in which these events occurred circa 350 BCE. The Arctic and Antarctic circles were also set by the solstices, indications of the northern- and southernmost latitudes that experience a full polar day (twenty-four hours of sunlight). The delineations here are theoretical boundaries derived from calculation, rather than direct observation.
In both the biblical and Aristotelian conception the Earth was perceived as the fixed, unmoving center of the Universe. Accordingly these diagrams were regarded as distinct but ultimately compatible perspectives, not indicators of fundamentally incongruent worldviews. Where the one was primarily concerned with the arrangement of the continents and their relation to scripture, the other was focused on geometric delineations in the underlying sphere. By the time this illustration was published, the complementary nature of the biblical and the Aristotelian conceptions had become an established tenet of canon law.