The Tractatus Vaticanus

If the part of human cognition which you find most fascinating is visualization of ideas, you're bound to have asked yourself when humans began doing this. And you'll probably have heard of my research, which has found that the key advances, at least in the West, took place during classical or late antiquity.

So how do we know when (or if) the Roman world invented information visualizations? Apart from the special case of fasti (a full-year calendar), which Sarah Bond raised in debate in October 2016, no antique stone-carving or papyrus survives that contains any visualization of abstract concepts.

What we instead rely on is the medieval evidence which does not explicitly attribute the discovery to the Romans, but provides enough clues for us to deduce the periods of origin of certain visualizations. One of the really important cases is the arbor juris, a matrix of kinship that works a little bit like those old-fashioned distance tables showing kilometres separating principal cities of a country.

Nailing down a date when the Romans invented the arbor juris and discovering what they called it is enormously hard, and that's why the digitization this week of a Vatican legal codex is so important.

Vat. lat.1352 is an 11th-century legal codex often referred to as the Tractatus Vaticanus which scoops up certain unique passages of legal scholarship, making it a historical resource of major importance. As so often, the moot point is whether its unattributed excerpta on legal issues draw on late-antique sources, or come from textbooks of more recent (medieval) date.

In particular there has been debate about its arbor juris diagram at folio 62r (above). Could the diagram and parts of the text below it be copied from a late-antique or even classical textbook of law? Historians have worried away at this problem for years. Referring to the Vat. lat.1352 drawing, the historian of ideas Gerhart B. Ladner wrote (1979):

[Max] Conrat, too, for different reasons, derives this stemma from the Sententiae Pauli and assigns to it provenance and date in Spain between the sixth and eighth centuries ... (op.cit. pp. 37 ff). It is possible that diagrammatic stemmata were a part of the Brevarium and also of the Notititia Dignitatum from the beginning (note 102, page 267, Google).

This is a cautious interpretation. Hermann Schadt, the great German authority on the arbor juris, was convinced that late antique books like the (lost) original Notitia Dignitatum really did contain an arbor juris. He also assembled a set of arguments for a late antique - and even a possibly classical Roman origin of the arbor juris by another name.

Although the text below the diagram refers to it as an arbor (tree), its form looks nothing like a tree. In the eighth line, the text reads: Ita tibi scala erecta est, quae a patre ad avum ...deducit. Schadt argues that it is not by chance that scala (ladder) is used here, but that this is probably the earlier term for such a diagram. Law texts associated with the Justinian Code (from 529) also use the terms scala and gradus (rung).

What is more, the existence of this and similar diagrams and of a common term to describe them would bolster the evidence that information visualization existed in late antiquity, that it was widely understood as a technique and that people had a terminology to use it, teach it and improve it.

Here is a list of the first 300 out of 1,733 links to newly online digitizations of microfilm of the Vat.lat. series. Further lists will follow through the week.  

1. Vat.lat.248 , LQ
2. Vat.lat.334 , LQ
3. Vat.lat.500.pt.1 , LQ
4. Vat.lat.500.pt.2 , LQ
5. Vat.lat.587.pt.1 , LQ
6. Vat.lat.691 , LQ
7. Vat.lat.717 , LQ
8. Vat.lat.718 , LQ
9. Vat.lat.829 , LQ
10. Vat.lat.890 , LQ
11. Vat.lat.970 , LQ
12. Vat.lat.973 , LQ
13. Vat.lat.989 , LQ
14. Vat.lat.1012 , LQ
15. Vat.lat.1033 , LQ
16. Vat.lat.1042 , LQ
17. Vat.lat.1044 , LQ
18. Vat.lat.1048 , LQ
19. Vat.lat.1054 , LQ
20. Vat.lat.1055 , LQ
21. Vat.lat.1056 , LQ
22. Vat.lat.1066 , LQ
23. Vat.lat.1071 , LQ
24. Vat.lat.1076 , LQ
25. Vat.lat.1083 , LQ
26. Vat.lat.1085 , LQ
27. Vat.lat.1110 , LQ
28. Vat.lat.1116 , LQ
29. Vat.lat.1118 , LQ
30. Vat.lat.1134 , LQ
31. Vat.lat.1140 , LQ
32. Vat.lat.1171 , LQ
33. Vat.lat.1187 , LQ
34. Vat.lat.1190 , LQ, Beuron Number 201 
35. Vat.lat.1191 , LQ
36. Vat.lat.1192 , LQ
37. Vat.lat.1195 , LQ, 
38. Vat.lat.1217 , LQ
39. Vat.lat.1242 , LQ
40. Vat.lat.1258 , LQ
41. Vat.lat.1261 , LQ
42. Vat.lat.1265 , LQ
43. Vat.lat.1266 , LQ
44. Vat.lat.1268 , LQ
45. Vat.lat.1271 , LQ
46. Vat.lat.1288 , LQ, codex unicus of Pedro Gallego's translation of Aristotle, De Animalibus (HT to @LatinAristotle)
47. Vat.lat.1294 , LQ
48. Vat.lat.1297 , LQ
49. Vat.lat.1308 , LQ
50. Vat.lat.1311 , LQ
51. Vat.lat.1321 , LQ
52. Vat.lat.1322.pt.A , LQ,  the flyleaf is recorded as a piece of 6th century parchment inscribed in Latin: TM 66106 = Lowe, CLA 1 8; Italy, Venetia - Verona (?)
53. Vat.lat.1328 , LQ
54. Vat.lat.1340 , LQ
55. Vat.lat.1341 , LQ, a very important church history compilation, the Collectio Hispana Gallica Augustodunensis, including details of the Second Council of Toledo
56. Vat.lat.1343 , LQ
57. Vat.lat.1345 , LQ, sole record of the 1120 Council of Nablus which established the crusader Kingdom of Jerusalem. Only this one copy, located in a church in Sidon, seemed to survive the Muslim reconquest of the Kingdom. This was in the papal library at Avignon by 1330.
58. Vat.lat.1348 , LQ
59. Vat.lat.1349 , LQ, 11th century Collectio Canonum et Conciliorum in Beneventan script
60. Vat.lat.1350 , LQ
61. Vat.lat.1352 , LQ, the famous Tractatus Vaticanus, of unknown Italian origin (above)
62. Vat.lat.1356 , LQ
63. Vat.lat.1357 , LQ
64. Vat.lat.1358 , LQ
65. Vat.lat.1359 , LQ,
66. Vat.lat.1360 , LQ, with a further arbor juris
67. Vat.lat.1361 , LQ
68. Vat.lat.1362 , LQ
69. Vat.lat.1364 , LQ
70. Vat.lat.1367 , LQ
71. Vat.lat.1377 , LQ
72. Vat.lat.1378 , LQ
73. Vat.lat.1408 , LQ
74. Vat.lat.1427 , LQ
75. Vat.lat.1431 , LQ
76. Vat.lat.1435 , LQ
77. Vat.lat.1437 , LQ
78. Vat.lat.1443 , LQ
79. Vat.lat.1464 , LQ
80. Vat.lat.1465 , LQ
81. Vat.lat.1466 , LQ
82. Vat.lat.1467 , LQ
83. Vat.lat.1468 , LQ, 11th century Glossarium. See Lowe
84. Vat.lat.1469 , LQ
85. Vat.lat.1478 , LQ
86. Vat.lat.1479 , LQ
87. Vat.lat.1480 , LQ
88. Vat.lat.1482 , LQ
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90. Vat.lat.1486 , LQ
91. Vat.lat.1491 , LQ
92. Vat.lat.1492 , LQ
93. Vat.lat.1495 , LQ
94. Vat.lat.1505 , LQ
95. Vat.lat.1511 , LQ
96. Vat.lat.1513 , LQ
97. Vat.lat.1515 , LQ
98. Vat.lat.1516 , LQ
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100. Vat.lat.1522 , LQ
101. Vat.lat.1528 , LQ
102. Vat.lat.1530 , LQ
103. Vat.lat.1532 , LQ
104. Vat.lat.1541 , LQ
105. Vat.lat.1548 , LQ
106. Vat.lat.1554 , LQ
107. Vat.lat.1560 , LQ
108. Vat.lat.1565 , LQ
109. Vat.lat.1570 , LQ
110. Vat.lat.1573 , LQ, Virgil, Bucolics, Georgics, Aeneid, 11th century Beneventan, according to Lowe
111. Vat.lat.1574 , LQ
112. Vat.lat.1575 , LQ
113. Vat.lat.1577 , LQ
114. Vat.lat.1580 , LQ
115. Vat.lat.1586 , LQ
116. Vat.lat.1589 , LQ
117. Vat.lat.1590 , LQ
118. Vat.lat.1593 , LQ
119. Vat.lat.1594 , LQ
120. Vat.lat.1595 , LQ
121. Vat.lat.1597 , LQ
122. Vat.lat.1598 , LQ
123. Vat.lat.1608 , LQ
124. Vat.lat.1610 , LQ
125. Vat.lat.1611 , LQ
126. Vat.lat.1621 , LQ
127. Vat.lat.1628 , LQ
128. Vat.lat.1631 , LQ
129. Vat.lat.1650 , LQ
130. Vat.lat.1653 , LQ
131. Vat.lat.1660 , LQ
132. Vat.lat.1661 , LQ
133. Vat.lat.1662 , LQ
134. Vat.lat.1663 , LQ
135. Vat.lat.1664 , LQ
136. Vat.lat.1669 , LQ
137. Vat.lat.1671 , LQ
138. Vat.lat.1673 , LQ
139. Vat.lat.1675 , LQ
140. Vat.lat.1678 , LQ
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142. Vat.lat.1694 , LQ
143. Vat.lat.1703 , LQ
144. Vat.lat.1706 , LQ
145. Vat.lat.1707 , LQ
146. Vat.lat.1720 , LQ
147. Vat.lat.1746 , LQ
148. Vat.lat.1762 , LQ
149. Vat.lat.1773 , LQ
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154. Vat.lat.1787 , LQ
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157. Vat.lat.1792 , LQ
158. Vat.lat.1795 , LQ
159. Vat.lat.1798 , LQ
160. Vat.lat.1802 , LQ
161. Vat.lat.1806 , LQ
162. Vat.lat.1812 , LQ
163. Vat.lat.1816 , LQ
164. Vat.lat.1837 , LQ
165. Vat.lat.1861 , LQ
166. Vat.lat.1869 , LQ
167. Vat.lat.1870 , LQ
168. Vat.lat.1875 , LQ
169. Vat.lat.1877 , LQ
170. Vat.lat.1880 , LQ
171. Vat.lat.1881 , LQ
172. Vat.lat.1887 , LQ
173. Vat.lat.1890 , LQ
174. Vat.lat.1893 , LQ
175. Vat.lat.1897 , LQ
176. Vat.lat.1904 , LQ
177. Vat.lat.1917 , LQ
178. Vat.lat.1932 , LQ
179. Vat.lat.1935 , LQ
180. Vat.lat.1936 , LQ
181. Vat.lat.1937 , LQ
182. Vat.lat.1938 , LQ
183. Vat.lat.1939 , LQ
184. Vat.lat.1940 , LQ
185. Vat.lat.1943 , LQ
186. Vat.lat.1945 , LQ
187. Vat.lat.1946 , LQ
188. Vat.lat.1974 , LQ
189. Vat.lat.1976 , LQ
190. Vat.lat.1984 , LQ
191. Vat.lat.1992 , LQ
192. Vat.lat.1994 , LQ
193. Vat.lat.1998 , LQ
194. Vat.lat.2000 , LQ
195. Vat.lat.2005 , LQ
196. Vat.lat.2010 , LQ
197. Vat.lat.2014 , LQ
198. Vat.lat.2027 , LQ
199. Vat.lat.2028 , LQ
200. Vat.lat.2030 , LQ
201. Vat.lat.2034 , LQ
202. Vat.lat.2044 , LQ, Lives of Jesus and the Popes, by Bartolomeo Platina (1474). Rome Reborn notes: Platina, librarian under Sixtus IV, compiled this set of sometimes quite critical biographies of the popes. This presentation copy of Platina's work contains corrections in his hand.
203. Vat.lat.2048 , LQ
204. Vat.lat.2050 , LQ
205. Vat.lat.2052 , LQ
206. Vat.lat.2066 , LQ
207. Vat.lat.2071 , LQ
208. Vat.lat.2072 , LQ
209. Vat.lat.2074 , LQ
210. Vat.lat.2075 , LQ
211. Vat.lat.2078 , LQ
212. Vat.lat.2085 , LQ, Metaphysica I of Aristotle, Latin translation (HT to @LatinAristotle)
213. Vat.lat.2090 , LQ
214. Vat.lat.2093 , LQ
215. Vat.lat.2094 , LQ, the unique manuscript containing a Latin translation by Theodore of Gaza of the zoological work of Aristotle (HT to @LatinAristotle), Historia animalium. On the grand frontispiece at fol 1r, see John Murdoch, Album of Science, where he comments that this is typical of Renaissance naturalism. Rome Reborn offers the page in colour (below) and adds: The richly decorated title page centers on an imaginative depiction of Aristotle at work surrounded by animals and a naked human couple--perhaps Adam and Eve. The medallion below portrays Sixtus IV and is inscribed sacricultor (keeper of sacred things); the medal above shows the Ponte Sisto and alludes to Sixtus's building program and role as ruler of the city of Rome.
     
     
216. Vat.lat.2115 , LQ
217. Vat.lat.2118 , LQ
218. Vat.lat.2121 , LQ
219. Vat.lat.2122 , LQ
220. Vat.lat.2123 , LQ
221. Vat.lat.2124 , LQ
222. Vat.lat.2132 , LQ
223. Vat.lat.2135 , LQ
224. Vat.lat.2136 , LQ
225. Vat.lat.2138 , LQ
226. Vat.lat.2139 , LQ
227. Vat.lat.2145 , LQ
228. Vat.lat.2146 , LQ
229. Vat.lat.2148 , LQ
230. Vat.lat.2153 , LQ
231. Vat.lat.2154 , LQ
232. Vat.lat.2159 , LQ, Blasius of Parma, Exposition and Quaestiones on Aristotle's Physics. John Murdoch, Album of Science, page 14, uses this as an example to explain the topic "Finding one's way around a medieval text", and reproduces folio 85r (frame 168) where the curly lines and pointing hands all make the arguments more tangible.
     
233. Vat.lat.2162 , LQ
234. Vat.lat.2163 , LQ
235. Vat.lat.2167 , LQ
236. Vat.lat.2185 , LQ
237. Vat.lat.2186 , LQ
238. Vat.lat.2190 , LQ
239. Vat.lat.2191 , LQ
240. Vat.lat.2214 , LQ
241. Vat.lat.2215 , LQ
242. Vat.lat.2222 , LQ
243. Vat.lat.2274 , LQ
244. Vat.lat.2280 , LQ
245. Vat.lat.2290 , LQ
246. Vat.lat.2306 , LQ
247. Vat.lat.2307 , LQ
248. Vat.lat.2317 , LQ
249. Vat.lat.2324 , LQ
250. Vat.lat.2343 , LQ
251. Vat.lat.2366 , LQ
252. Vat.lat.2369 , LQ
253. Vat.lat.2375 , LQ
254. Vat.lat.2378 , LQ
255. Vat.lat.2380 , LQ
256. Vat.lat.2381 , LQ
257. Vat.lat.2384 , LQ
258. Vat.lat.2388 , LQ
259. Vat.lat.2396 , LQ
260. Vat.lat.2416 , LQ
261. Vat.lat.2418 , LQ
262. Vat.lat.2426 , LQ
263. Vat.lat.2427 , LQ
264. Vat.lat.2434 , LQ
265. Vat.lat.2463 , LQ
266. Vat.lat.2482 , LQ
267. Vat.lat.2484 , LQ
268. Vat.lat.2486 , LQ
269. Vat.lat.2494 , LQ
270. Vat.lat.2509 , LQ
271. Vat.lat.2533 , LQ
272. Vat.lat.2539 , LQ
273. Vat.lat.2548 , LQ
274. Vat.lat.2569 , LQ
275. Vat.lat.2580 , LQ
276. Vat.lat.2593 , LQ
277. Vat.lat.2625 , LQ
278. Vat.lat.2639 , LQ, with an arbor juris
279. Vat.lat.2641 , LQ
280. Vat.lat.2648 , LQ
281. Vat.lat.2658 , LQ
282. Vat.lat.2659 , LQ
283. Vat.lat.2660 , LQ
284. Vat.lat.2666 , LQ
285. Vat.lat.2687 , LQ
286. Vat.lat.2691 , LQ
287. Vat.lat.2693 , LQ
288. Vat.lat.2694 , LQ
289. Vat.lat.2710 , LQ
290. Vat.lat.2712 , LQ
291. Vat.lat.2713 , LQ
292. Vat.lat.2714 , LQ
293. Vat.lat.2726 , LQ
294. Vat.lat.2727 , LQ
295. Vat.lat.2731 , LQ
296. Vat.lat.2740 , LQ
297. Vat.lat.2742 , LQ
298. Vat.lat.2759 , LQ
299. Vat.lat.2781 , LQ
300. Vat.lat.2782 , LQ

This is Piggin's Unofficial List number 98. If you have corrections or additions, please use the comments box below. Follow me on Twitter (@JBPiggin) for news of more additions to DigiVatLib.

Ladner, Gerhart B. ‘Medieval and Modern Understanding of Symbolism: A Comparison’. Speculum 54, no. 2 (1979): 223–56. Reprinted Rome, 1983 in: Ladner, Images and Ideas in the Middle Ages: Selected Studies in History and Art, vol 1 of 2. Ed. di Storia e Letteratura

Schadt, Hermann. Die Darstellungen der Arbores Consanguinitatis und der Arbores Affinitatis: Bildschemata in juristischen Handschriften. Tübingen [Germany]: Wasmuth, 1982.