For a development of the metaphysical sense of Beauty, read part one of this series here.

Secondly, there is also a practical sense of Beauty in the medieval world. Here the focus is not so much on the metaphysical nature of Being but rather on artistic quality; the demonstration of excellence or skill in an artifact. Aquinas writes in his Summa, ‘For a craftsman, as such, is commendable, not for the will with which he does a work, but for the quality of the work’ (ST I-II, Q.57, a.3 resp.).

The Medievals organized both the metaphysical and practical aspects of Beauty in terms of two primary attributes: what Umberto Eco calls an aesthetics of proportion (which is the quantitative nature of Beauty) and an aesthetics of light or luminosity (which is the qualitative nature of Beauty).

Briefly, an aesthetics of proportion involves the idea of ‘congruence’ (congruentia), balance, consonance, and harmony. This conception of harmonious proportion comes from Pythagoras, expanded by Plato, and developed in classical medical theory with the work of Galen, who links together Beauty and health. Beauty, like health, involves a harmonious proportion of the parts of the body in relation to the whole. This aesthetics of proportion was developed architecturally by the first century BC Roman architect Vitruvius, who was very influential from the ninth-century onwards for Medieval architecture.

Now I don’t know how many of you have seen the hour long Nova documentary entitled “Building the Great Cathedrals,” it’s a bit sensationalistic, claiming to have discovered secret codes in medieval architecture, but it is a nice primer on the importance of number and symmetry to gothic architecture. For example, the height of the Notre Dame church’s two levels measure 32.8 feet, but they used a different unit of measurement, the royal foot, which would have been a combined height of 60 royal feet (each level being 30). This 30:60 ratio has extraordinary significance for the medieval mind, which modeled the dimensions of Solomon’s Temple as 30 cubits to the first level, 60 cubits to the second level. According to Notre Dame chancellor Peter Comestor, in his Historia Scholastica, these numbers are built into Notre Dame. Similarly, Amiens Cathedral has a great square in the center of the cruciform floor plan, where each side measures 50 roman feet. If you recall, God told Noah to build an ark 50 cubits, and this Noahic square marks the central point of that part of the cathedral that is called the Nave, from which we get the word navy. And then when we measure the height of the cathedral, we find that it is 144 roman feet; heaven is the city of God with the height of 144 cubits (Rev 21:17). When the cathedral at Bovet was measured, it was also 144 roman feet. They were aiming at a celestial number. So, Solomon’s Temple, Noah’s ark, and the Celestial City provided sacred numbers that guided medieval architects in constructing heaven on earth.

And this architectural display of proportionality was complimented with the development of the Pythagorean conception of the music of the spheres. Harmonia was a cosmic term, as was symphonia, used to describe the structure and design of the cosmos. From this we get the concept of “The Music of the Spheres”: the idea that the stars and planets as they travel through space make beautiful music together. This paradigm played out through the classical world to the medieval period and the Renaissance, where the universe is full of meaning, of strange correspondences and grand ratios and harmonies. Boethius in the early sixth-century developed this in terms of three spheres or dimensions of music: musica mundana (music of the spheres), musica humana (harmony of the human body/soul), musica instrumentalis (instrumental music). And so the subsequent development of what would be called Gregorian Chant in the West by virtue of its systematization in the development of standardized notation in the tenth century, is but the sonic cosmology, the cosmic echoes, inherent in the universal shapes and proportions of the Medieval cathedrals. And so the metaphysic of Beauty and the practical application of the arts were inextricably bound up with one another in the Medieval world.

If harmonious proportionality was the quantity of medieval aesthetics, by the thirteenth century, luminosity was the central quality of medieval aesthetics. The thirteenth-century bishop Robert Grossetest (c. 1245) wrote: “Light is truly the principle of all beauty; light, as the principle of color, is the beauty and ornament of all that is visible.” Bonaventure, too, in his Reduction of the Arts to Theology, sees light as the principle of all beauty.

In our next and last post, we will see how all of these developments in Beauty informed medieval science.

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