Bartholomew’s Franciscan presentation of natura has been the subject of scholarly discussion. In the 1980s, David Greetham commented upon the mix of observation and allegory in ‘Properties’, and the way Bartholomew emphasises the natural world as a source of both wonder and praise. He finds a pleasing tension in the work between its ‘earthbound’ appearance and its moralising function.^[37] Peter Dronke’s important study of natura as a Christian concept traces its development over almost 1000 years, from late antiquity to the time of Bernard Silvestris and the school of Chartres.^[38] Roger French and Andrew Cunningham clarify the difference between the Franciscan and Dominican uses of the term natura and stress the fundamental importance to the Franciscans of particular biblical texts; above all, of Paul’s epistle to the Romans: ‘For the invisible things of him from the creation of the world are clearly seen, being understood by the things that are made, even his eternal power and Godhead.’ The properties of ‘the things that are made’ need to be understood as a window into the eternal world. For example, as French and Cunningham explain, light is of extreme importance to the Franciscans as the seraphic illumination which had descended upon Francis on Monte Verna. Light was therefore the clearest expression of nature and the primary Franciscan symbol of the unity and power of God.^[39]

In Book 2, Bartholomew devotes the second chapter to the properties of angels according to Pseudo-Dionysius, with some reference also to John Damascene, St Gregory and the Bible. He tells us that, according to Damascene, angels receive their light from God and reflect it upon those below. In this way they share with us the hidden sweetness of the goodness of God, received through contemplation and ‘tasting’ (contemplando et gustando).^[40] In Book 3, he describes the soul first of all as receptive to divine illumination.^[41] In Book 8, the subject of light receives specific and thoroughgoing treatment in a different context of knowledge, that of the earth and heavenly bodies. In the chapters on light in general, glowing light, light reflected and refracted, radiance, shadows and darkness, Bartholomew refers to a host of authorities, including Aristotle, Albumazar, Algazel, Augustine, Basil and Ambrose, to Calcidius’ commentary on Plato’s Timaeus, and to Pseudo-Dionysius On the divine names.^[42] This is a broad gathering of medieval statements concerning a key phenomenon of the physical and theological universe, in which Bartholomew does not adjudicate but simply makes available the spread of opinion. He does, however, balance the authority of Aristotle with that of Pseudo-Dionysius and other Neoplatonic writers, drawing the reader’s attention to the mystical and contemplative as well as physical properties of light. This would be appropriate for students familiar with the already-growing legend of Francis’s encounter with the seraph on Monte Verna.^[43]

This philosophy of nature, as that which our senses can apprehend as a first step towards God, is one which the Franciscan Bonaventure would later formulate in his Itinerarium mentis ad Deum. Bonaventure describes how the invisible things of God can be grasped intellectually through the senses, in contemplation of seven things: the origin, magnitude, multitude, beauty, plenitude, operation and order of the created world.^[44] According to Seymour, there is evidence of personal communication between Bonaventure and Bartholomew in a letter of 1266 addressing the older man as carissimo fratri Bartholomeo ministro Saxonie. ‘Properties’ may well have been available to Bonaventure in Paris by this time.^[45]

Bartholomew establishes early in the work the reassuring idea that life’s dangers and difficulties are counterbalanced by providential supports and remedies. He develops the theme of instability, change, growth and decay with much emphasis on the fecund as well as the degenerate nature of the unstable physical world, but teaches that amid this fecundity it is essential to be discriminating. Some ‘things’ are harmful, others remedial, and there are those that give us a feeling of closeness to God. Some of them require that we do our bit to make them useful. Book 17 contains chapters on the products of plants that can be processed, such as strong planed timbers for building ships and houses; paper and straw; a medicinal kind of pesto made of burdock leaves, nourishing porridge, raisins; bread-grains, yeast, ointment, olives and their oil.^[46] A long section of the Book is devoted to the distinctions that must be made between types of grapes and wine, some being beneficial but others spurious or harmful.^[47] The glosses indicate that these chapters were particularly resonant with associations with the Eucharist. They include references to the passion and blood of Christ, to the elevation of the Host, and to the nourishment and growth of charity and virtue: ‘Take note concerning the passion of Christ; the raising of the Host; the blood of Christ and its purity.’^[48] Glosses on the grape include pointers to fullness and fatness belonging both to the grape itself and to the idea of Christian love.^[49] Those on new wine point to novices, argument, and the danger of drunkenness and sensuality.^[50] In Book 17 there are also chapters on places where plants grow: within hedges, in prepared fields, and densely in groves, according to the fertility of the place.^[51] Bartholomew makes the chapter on the vineyard a focus for meditation on the plants, workers, good and destructive animals and sensory delights of the scene of earthly labour, while the chapter on the cellar tells us that the wine will be all the better for being kept in the cold and dark.^[52]