DanteSources: a Digital Library for Studying Dante Alighieri’s Primary Sources
10.6092/issn.2532-8816/7250
In questo articolo presentiamo DanteSources, una Digital Library il cui scopo è fornire servizi innovativi di supporto alla creazione, evoluzione e consultazione dell’enciclopedia digitale delle fonti di Dante Alighieri. DanteSources è dotato di servizi che consentono l’estrazione e la visualizzazione delle fonti primarie di Dante, i.e. opere di altri autori a cui Dante ha fatto riferimento nelle proprie opere. Il cuore del progetto è una base di conoscenza costruita attorno ad uno Schema RDF rappresentante le opere di Dante e le relative informazioni estratte da autorevoli commentari. A partire dal grafo è stato sviluppata l’applicazione DanteSources, che permette agli utenti di estrarre e visualizzare i contenuti sotto forma di grafici e tabelle. La metodologia e il tool realizzato sono di facile riutilizzo per la rappresentazione di conoscenza relativa a fonti primarie, siano esse italiane o internazionali.
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Mirko Tavoni
Umanistica Digitale
Semantic Web
DanteSources: a Digital Library for Studying Dante Alighieri’s Primary Sources
Text.Serial.Journal
https://umanisticadigitale.unibo.it/
Articles
2017-10-01
2017-09-24
2017-10-01
2019-03-05
Um. Dig.
Mirko Tavoni
2017/10/01
10.6092/issn.2532-8816/7250
Dipartimento di Filologia, Letteratura e Linguistica, Università di Pisa
2532-8816
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Semantic Web
en
DanteSources: a Digital Library for Studying Dante Alighieri’s Primary Sources
https://umanisticadigitale.unibo.it/article/view/7250/7008
    Umanistica Digitale - ISSN 2532-8816 - n.1, 2017
V. Bartalesi et al. - DanteSources: a Digital Library for Studying Dante Alighieri’s Primary
Sources
DOI: https://doi.org/10.6092/issn.2532-8816/7250



      DanteSources: a Digital Library for Studying Dante
                Alighieri’s Primary Sources

Valentina Bartalesi1 , Carlo Meghini1 , Daniele Metilli1 , Paola Andriani2 , e Mirko Tavoni2
1
    Istituto di Scienza e Tecnologie dell’Informazione “Alessandro Faedo”, Consiglio Nazionale delle
                                            Ricerche (CNR)
                2
                  Dipartimento di Filologia, Letteratura e Linguistica, Università di Pisa
           valentina.bartalesi@isti.cnr.it, carlo.meghini@isti.cnr.it,
               daniele.metilli@isti.cnr.it, paola.andriani@gmail.com,
                                     mirko.tavoni@gmail.com



        Abstract. We present DanteSources, a focused Digital Library that aims at building
        innovative services supporting scholars in creating, evolving and consulting a dig-
        ital encyclopaedia of Dante Alighieri’s works. DanteSources is endowed with Web
        services that allow extracting and visualizing data about Dante Alighieri’s primary
        sources, i.e. other authors’ works which Dante referred to in his own works. The
        heart of the digital library is a knowledge base built on an ontology that was devel-
        oped in the RDF/S language, representing Dante’s works and the knowledge about
        them, extracted from some authoritative commentaries. Finally, on top of this graph,
        we developed DanteSources, which allows users to extract and display the knowledge
        stored in the knowledge base in the form of charts and tables. The methodology and
        the tool we developed are easily reusable to represent the knowledge about primary
        sources of other authors of the Italian or the international literature.


        Abstract. In questo articolo presentiamo DanteSources, una Digital Library il cui
        scopo è fornire servizi innovativi di supporto alla creazione, evoluzione e consul-
        tazione dell’enciclopedia digitale delle fonti di Dante Alighieri. DanteSources è dotato
        di servizi che consentono l’estrazione e la visualizzazione delle fonti primarie di Dante,
        i.e. opere di altri autori a cui Dante ha fatto riferimento nelle proprie opere. Il cuore
        del progetto è una base di conoscenza costruita attorno ad uno Schema RDF rappre-
        sentante le opere di Dante e le relative informazioni estratte da autorevoli commen-
        tari. A partire dal grafo è stato sviluppata l’applicazione DanteSources, che permette
        agli utenti di estrarre e visualizzare i contenuti sotto forma di grafici e tabelle. La
        metodologia e il tool realizzato sono di facile riutilizzo per la rappresentazione di
        conoscenza relativa a fonti primarie, siano esse italiane o internazionali.


Keywords: Dante Alighieri, Digital Libraries, RDF/S, Semantic Web



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1 Introduction
One kind of knowledge that the scholars consider essential for of the study of old literary
works is the analysis of their primary sources, i.e. the works of other authors that an author
makes reference to in his/her texts. Usually, this knowledge is reported in modern paper
commentaries, which the readers use to understand several aspects of the literary works.
Having this knowledge available in a machine-readable form instead of in natural language
could allow using computers to make inferences that could facilitate and improve the study
to scholars, e.g. automatic calculation of the distribution of the primary sources and of the
authors cited in an old text.
     Our research is part of the Towards a Digital Dante Encyclopedia project, an Italian
National Research project supporting scholars in formally expressing the knowledge about
primary sources presented in Dante Alighieri’s works and more generally in literary texts.
In order to represent this information we (i) created an ontology providing a formal rep-
resentation of the terms required for expressing knowledge about the primary sources, and
(ii) develop a semantic Digital Library (DL) based on the ontology that allows scholars to
make inferences on the collected data and visualize them in a friendly and easy way.
     In the Digital Humanities field, there are ontologies focusing on different aspects of
textual information but, up to now, an ontology for representing knowledge about primary
sources of literary texts has not been developed yet. For this reason, we created an ontology in
the RDF/S language [13] to represent Dante’s works and the knowledge about their primary
sources. To develop the ontology, we reused existing vocabularies where possible, in order to
maximize its interoperability, adding our own classes and relationships for the representation
of the categories of knowledge that were not addressed by the existing ontologies. For a
detailed description of the ontology we refer to [7].
     Then, we populated the ontology with the knowledge extracted from some authorita-
tive commentaries, obtaining an RDF knowledge base. On top of this knowledge base, we
developed DanteSources,1 a focused Digital Library that allows extracting and visualizing
information on Dante Alighieri’s primary sources in form of charts and tables and in CSV
format. In this paper we describe the DL DanteSources and the methodology we used to
develop it.
     The paper is structured as follows: Section 2 reports a review of related works; in Sec-
tion 3 the functionalities of DanteSources are described in detail; in Section 4 conclusions
are reported.


2 Related Works
In the Semantic Data Modeling field, several ontologies have been developed in order to
represent textual knowledge. Up to now, a formal ontology for representing knowledge
about the primary sources of literary texts has not appeared yet. So we developed a new on-
tology taking into account the existing ones, reusing their classes and properties in order to
improve its interoperability. In particular, we reused, among others, some classes and prop-
 1
     http://dantesources.org




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erties from authoritative ontologies like FRBRoo [15], SKOS [14], Dublin Core,2 DoCo
[16], and the CIDOC CRM [8].
     In the Digital Humanities field, several projects about Dante Alighieri and his works
have been published online. Most of them offer digital editions of Dante’s works with com-
mentaries, textual search, and multimedia resources. For example, the Dartmouth Dante
Project (DDP)3 was launched in 1985 with the aim of publishing the full searchable text
of the Divine Comedy and several of its commentaries in digital format [10]. On top of the
DDP in 2013 the web application Dante Lab4 was developed. This application allows the
concurrent visualization of the original text of the Comedy, some translations and more
than 75 commentaries. The Princeton Dante Project5 includes the full searchable text of
the Divine Comedy, Dante’s minor works, several commentaries and multimedia resources
[11]. Digital Dante6 offers the full text of all Dante’s works with commentaries, illustra-
tions and recorded readings. It also features a subproject called Intertextual Dante,7 the first
digital attempt at connecting passages of Dante’s works with the corresponding fragments
of cited primary sources. However, the project is limited to the works of the Roman poet
Ovid [17]. Recently, two Italian research projects have been published: DanteSearch8 and
Dante Medieval Archive (DaMA).9 DanteSearch is a complete lemmatization, grammatical
and syntactic annotation of Dante’s works allowing users to perform morphological and
syntactic queries on the full text of the author’s works. On the other hand, DaMA is a
digital archive containing the full text of Dante’s works, commentaries and several primary
sources in XML-TEI10 format.
     With the advent of the Semantic Web, several projects were started with a focus on the
application of the new semantic technologies (RDF, OWL)11 to the Humanities. For in-
stance, [9] describes a semantic model to connect repertoires of poetic writings. [18] presents
an ontology for the 3D visualization of cultural heritage; [12] describe an ontology for anno-
tating geographical places in texts. In this context, we developed DanteSources DL, which
uses the technologies of the Semantic Web to represent the knowledge included in the works
of Dante Alighieri, focusing on primary sources.


3 The Digital Library DanteSources
First of all, in order to develop the DL DanteSources, we analyzed the representation re-
quirements about citations of primary sources, in collaboration with a Dante’s expert. Then,
on the basis of this analysis, we created an ontology responding to the requirements, pro-
viding a formal representation of the terms required for expressing knowledge about the
 2
     http://dublincore.org/documents/dcmi-type vocabulary/index.shtml
 3
     http://dante.dartmouth.edu
 4
     http://dantelab.dartmouth.edu
 5
     http://etcweb.princeton.edu/dante/
 6
     http://digitaldante.columbia.edu
 7
     http://digitaldante.columbia.edu/digital-projects/intertexual-dante/
 8
     http://www.perunaenciclopediadantescadigitale.eu:8080/dantesearch/
 9
     http://perunaenciclopediadantescadigitale.eu/istidama/
10
     http://www.tei-c.org/index.xml
11
     https://www.w3.org/TR/owl2-overview/


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primary sources, using the RDF/S Semantic Web language. After this phase, we developed
a semi-automatic tool for populating the ontology and storing the resulting data in a knowl-
edge base. Finally, we developed DanteSources, a web application running on top of the
knowledge base that allows making inferences on the contents of the knowledge base and
visualizes them in a friendly and easy way, using charts and tables.
    The authoritative commentaries used to populate the ontology are the following: Vita
Nova [5], Vita Nuova [6], De vulgari eloquentia [2], Convivio [1], Monarchia [3], and Rime
[4]. DanteSources is developed in Java using JavaScript and Ajax functions. The DL ex-
tracts knowledge by running SPARQL queries on the RDF knowledge base. DanteSources
shows the knowledge about the primary sources cited by Dante in the form of tables and
column bar charts. In particular, we used the Highcharts12 JavaScript library to implement
these charts. Highcharts allows exporting the charts in various well-known formats: PDF,
PNG, JPEG, SVG. Furthermore, we implemented an additional JavaScript function allow-
ing users to automatically export and download all the data in CSV format.13 This feature
was particularly appreciated by the scholars since it allows obtaining and managing raw data
in a simple and standard format, in order to apply further data analyses in addition to the
ones already provided by the DL.




                 Fig. 1. Distribution of the ten most-cited primary sources in Rime


    Currently, DanteSources makes available eight different predefined SPARQL queries to
extract data. They can be distinguished into three different groups. The first group includes
12
     http://www.highcharts.com/
13
     http://www.w3.org/2013/05/lcsv-charter.html


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three queries. In order to make these queries, a search form allows users to choose either
one Dante’s work or all his works and, in addition, a specific subpart of the work (e.g. a
book). The queries produce column bar charts regarding the distribution of the works, the
authors and the thematic areas cited by Dante. For example, Fig. 1 shows the chart of the
distribution of the ten most-cited primary sources in Dante’s work Rime.
     Further information about primary sources, authors and thematic areas can be visualized
by clicking on their names on the charts. In particular, for each primary source the DL shows
a table reporting information about: (i) the book, (ii) the chapter, (ii) the paragraph or verse
and (iv) the fragment of the Dante’s work in which the primary source is cited, (v) the type
of reference, (vii) the reference to a fragment of the primary source cited in the commentary,
(viii) the thematic area and (ix) the author of the primary source. An example of this table,
related to Brunetto Latini’s work Tesoretto, is shown in Fig. 2.




         Fig. 2. Table listing the first four citations of Brunetto Latini’s Tesoretto in Rime


    Similarly, when clicking on the name of a cited author, a table reporting all the works
of that author cited in the Dante’s text chosen by the user is shown. Furthermore, for each
primary source the DL reports the book, the chapter (or poem) and the paragraph (or verse)
of the Dante’s text in which the author is cited. Fig. 3 shows an example of table related to
cited author Brunetto Latini.
    The same happened for the thematic areas, indeed clicking on one name the user obtains
the following information: the primary sources included in that area, their authors and the


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        Fig. 3. Table listing the first ten citations of Brunetto Latini in De vulgari eloquentia


book, chapter (or poem) and paragraph (or verse) of the Dante’s work where the thematic
area is cited. Fig. 4 shows an example of table related to thematic area Aristotelianism.




Fig. 4. Table listing the first ten citations of thematic area Aristotelianism in the first book of Monar-
chia


     The three queries of the second group allow visualizing several charts that report the
distribution of a particular primary source, a cited author or a thematic area respectively.
     The data regarding the distributions are not only available for an entire Dante’s work,
like Convivio, but also for its subparts like books, chapters or poem. Indeed, by clicking on


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one bar in the chart representing the distribution of the information onto a Dante’s work, it
is possible to visualize information about its subparts. For example, it is possible to visualize
the distribution of the selected knowledge in all three books of Dante’s Monarchia and also
in each chapter of the first book of Monarchia. Fig. 5 shows the distribution of a primary
source on three different levels: all Dante’s works (a), one particular Dante’s work (b), a
subpart of a Dante’s work (c).




Fig. 5. The distribution of Summa Theologiae in all Dante’s works (a), in the three books of Monarchia
(b) and in the chapters of the first book of Monarchia (c).


    The last group includes two queries that visualize the distribution of the three types
of reference to primary sources: explicit, strict and generic, focusing on either on Dante’s
works or on all primary sources written by a specific author. Indeed, with the support of
Dante’s experts, we defined three types of reference:
    1. explicit, if the reference is explicitly made by Dante, e.g. “As the Philosopher says
at the beginning of the First Philosophy”, where the Philosopher is Aristotle and the First
Philosophy is Metaphysics;




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    2. strict, if the reference is indicated by a scholar and refers to a specific work, e.g. “SI
MANUCA: it is the bread of the angels, the manna as called in the Old Testament (Ps. 77,
25 Panem angelorum manducavit homo)”;
    3. generic, if the reference is indicated by a scholar, and refers to a concept (e.g. Medieval
comments to Aristotle’s works).




              Fig. 6. The distribution of the three types of reference in Dante’s works


    Fig. 6 shows the distribution of the three types of reference in a specific primary source.
By clicking on the bars of the chart, the data regarding the distribution of the types of
reference are available both for an entire Dante’s work and for its subparts, i.e. books and
chapters. Fig. 7 shows the distribution of the three types of reference in all primary sources
written by a specific author, Albertus Magnus.


4 Conclusions
In this paper we have presented DanteSources, a Digital Library that allows free access to
the knowledge on Dante Alighieri’s primary sources. In order to represent this knowledge,
we developed an ontology, expressed in RDF/S, on top of which DanteSources was created.
The main advantages of using an ontology instead of a traditional database are the following:
(i) it allows researchers to add classes and relationships thereby refining the ontology, (ii)


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Fig. 7. Distribution of the three types of reference in all primary sources authored by Albertus Magnus


the ontology can be linked to other ontologies to extend the represented domain, (iii) any
user can download and use the knowledge base freely, using the paradigm of Linked Data.
    Furthermore, this is the first time that the knowledge about Dante’s primary sources is
coded in digital format. This availability allows improving and making the scholars’ searches
more efficient. Eventually, the digitization of the knowledge about primary sources and its
visualization in form of charts and tables allow the scholars to have a complete overview
of the data. This simplifies the study by the scholars on the evolution in time of Dante’s
cultural background, also in relation with the diverse stages of his biography.
    The ontology, the tool to populate it and the developed DL are easily and freely reusable
in order to represent the knowledge about primary sources of other authors of the Italian
and international literature.
    DanteSources was the winner of the Digital Humanities Awards 201514 in the category
Best DH Tool or Suite of Tools.15


References
1. Alighieri, Dante. “Convivio.” In Opere, a cura di Gianfranco Fioravanti, Vol. 2. Milano: Mon-
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2. Alighieri, Dante. “De Vulgari Eloquentia.” In Opere, a cura di Mirko Tavoni, Vol. 1. Milano:
   Mondadori, 2011.
3. Alighieri, Dante. “Monarchia.” In Opere, a cura di Diego Quaglioni, Vol. 2. Milano: Mondadori,
   2014.
4. Alighieri, Dante. “Rime.” In Opere, a cura di Claudio Giunta, Vol. 1. Milano: Mondadori, 2011.
14
     http://dhawards.org/dhawards2015/
15
     http://dhawards.org/dhawards2015/results/


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5. Alighieri, Dante. “Vita nova.” In Opere, a cura di Guglielmo Gorni, Vol. 1. Milano: Mondadori,
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