Historians of Renaissance and early modern philosophy often try to give a unity to their subjects by framing the creative elements of these periods as engaging in a revolt against “scholasticism”. However, this only gives as much intelligibility to the Renaissance as is granted to its foil, and historians usually assign scholasticism any negative quality needed to keep the narrative going; it can be mindlessly dogmatic or aridly intellectual or both at once, despising all nature or assigning fanciful hierarchies within it, servile or unfaithful to Aristotle, holding an opinion of man that is irrationally low (when the opponent is humanism) or high (when the opponent is science). Ernst Cassirer in his 1963 book The Individual and the Cosmos in Renaissance Philosophy tries to fit his material into this standard narrative, but he provides a great deal of interesting material, so that a more interesting story begins to emerge.
Cassirer’s exemplary Renaissance philosopher is Nicholas of Cusa (Nicholas Cusanus), the idiosyncratic Christian neo-Platonist who smashed the medievals’ hierarchical universe to stress the incomparability of God, the Absolute and Infinite, the confluence of opposites. He imagined the Earth in motion (which he seems to suggest is relative) in an infinite universe with no center but God, a physical infinity to which corresponds the intentional infinity of the human mind–whose operation is now conceived primarily in terms of measuring and comparing. From Cusanus, Cassirer expands to cover a number of other characters: Platonists like Marsilio Ficino and his Florentine Academy, humanists like Petrarch and Pico della Mirandola, proto-Hegelians like Charles de Bovillus, and those climbing toward a scientific approach to nature like Leonardo and Galileo.
Several things become clear. The recovery of Plato’s dialogues made Plato a rallying point against Aristotle for a rather diverse group of thinkers. Why should this be? Petrarch’s preference for Plato over Aristotle and his scholastic followers was primarily aesthetic and therefor frivolous. Most of the others had disagreements with Aristotle but ones that hardly seem to take them outside of the orbit of scholasticism, i.e. not farther from Aquinas or Ockham than these two are from each other. One often encounters an assumption that separation from scholasticism means approach to secularism, an assumption popular because it is so congenial to both secularists and scholastics. I’ll therefore mention that most of these thinkers gave every impression of being ardent Christians. And yet, they did consider themselves at war with the Aristotelian schoolmen.
Then Cassirer, in the final chapter, gives a revealing fact.
To understand the transformation that takes place with the beginning of the philosophy of the Renaissance, we must keep in mind this opposition, this tension, which already existed in the medieval system of life and learning. Despite all the attacks it had suffered in the classical systems of Scholasticism, the theoretical foundation of Averroism seemed to be completely unshaken in the 14th and 15th centuries. For a long time, it was the reigning doctrine in the Italian universities. In the actual academic citadel of Scholastic studies, in Padua, Averroistic doctrine maintained itself into the sixteenth and seventeenth centuries. But gradually, a counter movement emerges ever more clearly. Characteristically, this counter movement is by no means restricted to the environs of the school, but rather receives its strongest impulses from other quarters. The men of the new humanistic ideal of culture and of personality are the first to sound the call to do battle against Averroism. Here, too, Petrarch leads the way…The artist and virtuoso who rediscovered the inexhaustible wealth and value of ‘individuality’ now sets up his defenses against a philosophy that considers individuality to be something merely casual, something purely ‘accidental’. And Augustine becomes his guide in this battle.
Well, if Averroism dominated the Italian universities (a fact which is new to me), and that’s what the humanists meant by “Aristotelianism”, then it becomes very clear how the writings of Plato–with their support for personal immaterial immortality–could serve as a philosophical rallying point to the opposition, and also how a literary movement devoted to individuality would be so adamantly a part of this opposition. Replace “the Renaissance was a rebellion against scholasticism/medievalism” with “the Renaissance was a rebellion against Averroism”. It would take a good deal of confirming evidence before we believe it (though Cassirer does continue with citations to attacks on Averroism from many of the Renaissance greats from Cusanus on), but at least this new narrative makes sense.
In the same chapter (the best of the book) Cassirer relates the Renaissance’s stumbling toward the scientific method. The misfires are particularly informative. One finds that prizing experience over a priori reasoning isn’t enough, at least given a medieval credulity to reports and a tendency to express observations in magical categories. A commitment to a belief in a universal rational order of the universe isn’t enough; that led to painstakingly systemized astrology. (Astrology made a big comeback in the High Middle Ages / Renaissance with the influx of pagan and Muslim learning. Once again, the Church and the humanists were on the same side in the fight against it.) Cassirer thinks what was missing was a mathematical approach to nature, and this came from scientist-artist like Leonardo da Vinci and their attention to form. However, if focus on form is what you want, then Aristotle is your man. And yet, the great men of the scientific revolution like Copernicus, Galileo, and Kepler were definitely Platonists, not Aristotelians, despite the scholastic preference for Aristotle. What gives?
The main difference between Plato and Aristotle is that the former makes the intelligibility of the world transcendent, the latter immanent. Imagine you were Galileo trying to understand how bodies fall. For an Aristotelian, action follows being. To learn how a body falls, you must first ask what is the nature of that body, given by its substantial form. You would not expect there to be a general rule about how things fall, because different things have different natures and hence different principles of motion. (cf. Nancy Cartwright’s “dappled world”) The idea of general laws of motion is much more natural in a Platonic/transcendent framework.
So there’s a story that makes quite a bit more sense than the standard story. The fight against Averroism promoted Platonism, and Platonism gave us science. That’s the intellectual story of the Renaissance.