Variants Mining. Investigazioni computazionali sulle varianti d'autore: un confronto tra Leopardi e Manzoni
10.6092/issn.2532-8816/12627
Qual è il significato delle correzioni d’autore? Variants Mining cerca di rispondere a questa domanda tramite l’acquisizione di dati empirici sul pensiero creativo. Tramite una previa categorizzazione delle modalità di correzione autoriale, lo studio mira a fornire agli studiosi statistiche sulle correzioni, calcolate in maniera automatica a partire dal PDF dell’opera o dalla codifica TEI della rispettiva edizione critica. L’utilizzo di grafiche di Data Visualization permette infine di rendere il risultato immediatamente comprensibile. L’analisi comparativa delle modalità correttorie che ne risulta potrebbe favorire la nascita di nuove letture critiche volte a svelare i processi creativi degli autori e valutare la possibilità di considerare le correzioni come pattern ricorrenti. Questa metodologia innovativa si propone inoltre di stimolare gli utenti verso un approccio più consapevole all'evoluzione storica del pensiero creativo servendosi di una rappresentazione immediata dei risultati. L’analisi dei due case-study scelti per lo studio pilota, i Canti di Giacomo Leopardi e I promessi sposi di Alessandro Manzoni, permetteranno di comprendere le differenze esistenti tra i due autori chiave del Romanticismo italiano e tra poesia e prosa intese come dispositivi narrativi.
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Variants Mining. Computational investigations on authorial variants: a comparison between Leopardi and Manzoni
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Variants Mining. Computational investigations on authorial variants: a comparison between Leopardi and Manzoni
https://umanisticadigitale.unibo.it/article/view/12627/12827
    Umanistica Digitale – ISSN: 2532-8816 – n. 10, 2021
A. S. Lippolis, G. Totaro – Variants Mining. Computational investigations on authorial variants:
a comparison between Leopardi and Manzoni
DOI: http://doi.org/10.6092/issn.2532-8816/12627



Variants Mining. Computational investigations on authorial
variants: a comparison between Leopardi and Manzoni

                               1
                                Anna Sofia Lippolis, 2Gabriella Totaro

                                       University of Bologna, Italy
                                     1,2

                           1
                            annasofia.lippolis@studio.unibo.it
                            2gabriella.totaro@studio.unibo.it




       Abstract

What is the meaning of the authors’ interventions on their own texts? Variants Mining aims to
answer this question by gaining empirical insight into creative thinking. The research focuses on
pre-established categories of authorial variants to provide scholars with statistics of corrections,
automatically computed starting from either the PDF document or the TEI encoding of the
referring critical edition of the text. Finally, the output is made easily understandable thanks to
a specifically tailored data visualization tool. This innovative comparative analysis on the
correction modalities would allow to provide new philological readings that shed light on the
creative process of different authors and assess if these interventions can be read as recurring
patterns. Therefore, this methodology promotes a more conscious insight on the historical
evolution of the authorial thought through a straightforward representation. A pilot analysis will
focus on the case studies of Giacomo Leopardi’s Canti and Alessandro Manzoni’s I promessi sposi
to understand the difference not only between the two key authors of Italian Romanticism, but
also between poetry and prose.
Qual è il significato delle correzioni d’autore? Variants Mining cerca di rispondere a questa
domanda tramite l’acquisizione di dati empirici sul pensiero creativo. Tramite una previa
categorizzazione delle modalità di correzione autoriale, lo studio mira a fornire agli studiosi
statistiche sulle correzioni, calcolate in maniera automatica a partire dal PDF dell’opera o dalla
codifica TEI della rispettiva edizione critica. L’utilizzo di grafiche di Data Visualization permette
infine di rendere il risultato immediatamente comprensibile. L’analisi comparativa delle modalità
correttorie che ne risulta potrebbe favorire la nascita di nuove letture critiche volte a svelare i
processi creativi degli autori e valutare la possibilità di considerare le correzioni come pattern
ricorrenti. Questa metodologia innovativa si propone inoltre di stimolare gli utenti verso un
approccio più consapevole all'evoluzione storica del pensiero creativo servendosi di una
rappresentazione immediata dei risultati. L’analisi dei due case-study scelti per lo studio pilota, i
Canti di Giacomo Leopardi e I promessi sposi di Alessandro Manzoni, permetteranno di

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comprendere le differenze esistenti tra i due autori chiave del Romanticismo italiano e tra poesia
e prosa intese come dispositivi narrativi.



       Introduction

Can authorial manuscripts, also known in Italian as “scartafacci”, reveal something about the
creative thinking of an author? Discarding the teleologism that characterized traditional
philological hypothesis, the revolutionary approach to literary texts furthered by Gianfranco
Contini ([12]) made it possible to shed light on the hermeneutic, linguistic and philosophical
value of authorial variants and to consider them as clues of the subjective approach to the act of
writing.
While boasting a century-old tradition, it is only due to the foundational contribution of Dante
Isella that Authorial Philology has been recognized as a subject in its own right compared to the
more traditional “philology of the copy”, which differs in terms of purposes and methodologies.
The first essential distinction between the two disciplines concerns the conception of the critical
apparatus, which also reflects their different goals: while in Textual Criticism it is aimed at
representing in a synthetic and transparent way the variants of the witnesses in the process of
reconstruction/amendment of the archetype, to allow the reader to understand the choices of the
publisher in the total absence of evidences of the author’s ones, the method of Authorial
Philology shows all the genetic phases of the text, from the very first creative idea of the author
until his or her last will.
Other than providing the discipline with an official definition, in his 1987 essay Le Carte
Mescolate. Esperienze di Filologia d’autore ([18]), Dante Isella developed a formalization method
to represent authorial corrections based on their critical interpretation that has served as a model
for all the following critical editions.
Since manuscripts are made up of many heterogeneous elements that must be compared to be
efficiently analyzed, Isella grouped variants into different categories based on the function they
performed in the manuscript and provided an individual representation for each of them.
Genetic and evolutive variants, which are those affecting the final reading, are distinguished
from, on the one hand, alternative or intra-textual variants, that co-exist with the text as the
author had not yet reached an undeniable decision about them; on the other hand, meta-textual
notes, which constitute a separate category of linguistic references and critical or compositional
notes written by the author ([20]).
The streamlined system developed by Isella made it possible to represent all the detected
correcting phenomena: exclusive abbreviations are associated with single variants (such as
deletions, insertions, displacements, variants taken from others, overwritten and underwritten
variants), whereas numeric and alphabetic exponents identify phases and sub-phases that allow
tracing the evolution of syntactic units.



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                                                 a comparison between Leopardi and Manzoni

The resulting apparatus allows scholars to represent all the correction phenomena in a diachronic
and systemic way, granting the reader the possibility of identifying the stratification of the
editorial process. Thanks to this innovative framework, critical apparatuses do not present
corrections transcribed in a “diplomatic” form but are rather critically interpreted, significantly
diverging from the model used by similar philological traditions such as Critique génétique ([23]).
Given the variety of available documentary material and case studies in the Italian literary
tradition, and the tendency to study them in an isolated way, a comparative analysis of the
process lying behind the composition of these works from the perspective of Authorial Philology
has never been carried out before. Nevertheless, this approach would prove useful to enter the
author’s workshop and deeply understand their poetics and the creative process starting from
material evidence.
Recent studies have shown the possibility to find patterns in correction on such grounds. Starting
from the consideration of manuscripts as “geographical maps”, used to keep track and categorize
the elaborative processes of the authors, Paola Italia ([22]) proposed a first typology based on
some famous cases of Italian literature and highlighted the possible ecdotic implications of such
approach. A first distinction to be outlined is that among the types of authors who correct “by
map” or “by compass”: the essential difference, therefore, lies in the planning of the writing that
translates into the manuscript page, transforming it into a conceptual map or into the battlefield
of ideas that compete for the physical space of the page.
Since authorial corrections can be considered clues to investigate the creative thinking of an
author, performing a comparative analysis of the different correction modalities would thus allow
to assess whether authorial interventions depend on personal attitudes or are influenced by
external events.



       Authorial Philology and Digital Approaches

The digital turn has led to a real methodological revolution in philological research emphasizing
the dynamic character of literary texts and their social value. Nevertheless, because of the
apparatuses’ complexity and their relatively recent affirmation, so far, digital approaches to
Authorial Philology have been mainly focused on investigating the shift that the brand-new
editorial practices have produced in the centuries-old tradition of Textual Criticism, either by
enhancing it or by emphasizing its criticalities, through the aid of scientific disciplines and new
technologies. In particular, almost all the attempts in this field have been aimed at representing
the history of the textual tradition, rather than at reconstructing the process behind an author’s
rewriting interventions on their texts.
Instead of trying to render the textual movement as a whole, Variants Mining focuses on its
minimum underlying entities, namely authorial interventions, to emphasize their importance in
defining the evolution of the author’s self-representation.



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This work thus deviates from this widespread approach for it results reductive when compared
to the whole process of interpretation of a text, which provides a complete understanding of a
literary work beginning from the representation level. Accordingly, Variants Mining aims at
taking advantage of the current coexistence between analog and digital philology by exploiting
the transition process using traditional formulas of philological apparatuses to provide a
comprehensive evidence-based analysis of pre-established categories of authorial corrections,
starting either from the PDF version of the critical apparatus of literary works or from their TEI-
encoded versions, when available.
It sets an even more ambitious goal compared to current developments in the field, that is, to
prove that the digital medium could enhance the representation of authorial variants, and also
favor quantitative analyses, allowing scholars to understand more intuitively how an author
works, and gain empirical insight on their philological hypotheses in the awareness that this
could contribute not only to extend traditional philology to new perspectives of analysis but also
facilitate the social democratization of philological knowledge.
The rationale behind the apparatuses of Authorial Philology, together with the high standard of
technical development reached in the XX century, makes it worth the attempt to analyze them
using computational methods. By exploiting a highly multidisciplinary approach that integrates
philology, cognitive philology, and computer science, and uses new technologies as
methodological framework of analysis and as means of information visual representation, the
project not only aims at proposing innovative theoretical insights, but also at achieving scientific
verifiable results through an evidence-based analysis and empirical insight into the material
premises of creativity.



       Related work

Automatic processing of a critical apparatus is a brand-new field of research. However, similar
work concerning the automatic representation and processing of corrections, derived by a custom
TEI model of the text, has already been carried out starting from different premises and a
different purpose. For instance, in the Samuel Beckett Digital Manuscript Project (SBDMP, [36]),
the number of added, deleted and modified words is displayed through a pie chart for each
genetic edition of Beckett’s works, along with the possibility to compare one another, first drafts
versions and a broader view of the full genetic dossier. This choice of visualization corresponds
to complex editorial principles which mirror Beckett’s poetic anxiety and attitude towards
thematic despair and failure topic-wise. Both additions and deletions are indeed encoded in the
project with attributes referring to the author of the intervention (Beckett, anyone or unknown):
its place (up to nine possibilities), the writing tool used and a particular “type” value for the case
of alternative variants. Specific tags are also employed as children of the main ones to cover the
cases of restorations of deletions (the “restore” tag), or to add annotations to signal further
information about the text (“metamark”).


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A. S. Lippolis, G. Totaro – Variants Mining. Computational investigations on authorial variants:
                                                 a comparison between Leopardi and Manzoni

Another proposal of automatic processing of corrections concerns the automatic identification
of types of alterations in historical manuscripts for the case study of the digital scholarly edition
Berlin intellectuals 1800-1830 ([26]), a collection of letters and texts representing communication
conditions and developments for intellectuals in that specific historical and cultural time frame.
The input for this analysis was a custom diplomatic TEI transcription of the manuscripts. Like
the SBDMP, in fact, the digital edition gives value to interoperability, so that a reader can both
see additions and deletions of the text as well as material elements of the manuscript relevant to
its contextual comprehension ([2]). The analysis thus exploits recent machine learning
techniques to help categorize content-related alterations into mistakes, stylistic and moral
changes from such a labelled dataset.
Both projects show the multiple perspectives of analysis that can be derived from a manual TEI
encoding of the authorial corpus, as the transcription and its automatic analysis show the attempt
to find a balance between objectivity and applicability to the specific resource and, at the same
time, between a general impartial transcription of the object and the availability of critical
elements to enable its understanding. Apart from the difficulty to achieve an efficient solution in
a short time period, problems of this operation concern its being time consuming and requiring
dedicated work.
Instead, by exploiting the categories of Authorial Philology, Variants Mining allows individual
scholars to extract immediately granular information, which can be then grouped into aggregate
categories of analysis, and using open-source tools only, hence the use of digitized critical
editions—whose choice would fill the gap between born-digital texts and printed ones— will be
taken as the main reference for the analysis and the proposal of a TEI model will be outlined in
the view of scalability.
So far this task requires a completely different approach to critical apparatuses, which is based
on the ways corrections are made by the author rather than on their content thus designating a
“style” of corrections.
Moreover, the lack of related work in the field requires addressing a theoretical problem that is
implicitly the elephant in the room in the field of computational studies applied to literary
sources. Text criticism carried out on the results of a computational analysis claims an arbitrary
relationship between formal patterns and interpretation that is difficult to justify. In fact, formal
patterns are products of a posteriori interpretations, where the term has every time its own
meaning, thus a different position towards objectivity. It is true this sense of computational
approach is different from the traditional sciences’, and it has to be treated as such.



       Methodology

The first step of the methodology was to choose the categories of correction suitable to the
analysis. Thanks to a first qualitative analysis based on close reading and the principles of
Authorial Philology, categories of correction have been identified, which have then been grouped
into macro categories (immediate variants, late variants, additions). Whereas immediate variants
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are distinguished by late ones due to the indication of an intervention at the time of the
composition 1, additions are signs of a thematic or linguistic innovation.

        PDF preprocessing and automatic analysis of the critical apparatus
Because one of the main purposes of Variants Mining was to bridge a gap between paper and
digital editions, there were two main inputs for the analysis—the PDF version of the considered
work and its encoding in TEI. While the latter has been already exposed in De Biase, Lippolis
and Totaro ([14]), the development of the project on the basis of the digitized document requires
further explanation steps.
Before delving into the analysis, it is important to mention that PDF, which stands for Portable
Document Format, is not meant to be processed. It was created by Adobe in 1993 as a layout-
based format that preserved content and configuration of documents in view of the print while
being able to be exchanged platform-independently. As a result, it has been defined as a
“collection of objects which describe how one or more pages must be displayed” ([4]: 4): the
semantic building blocks of the text are non-existent, since the data related to them is conceived
as characters independent from one another, each with a specific position on the page. As such,
while the human eye naturally recognizes words, paragraph boundaries and semantic roles within
the page, text understanding for the machine stems from instructions grouping letter sizes and
positions into words and paragraphs. In this way, content ordering and presentation ordering are
two separate levels of document identification.
Furthermore, as PDFs can include nonstandard fonts and encoding, as well as extra spaces
between letters or, vice versa, not enough space, it was necessary to convert the file in XML
format so that every information related to each character could be preserved precisely as it was.
In the case of the apparatus of the critical edition, this meant to maintain superscripts of
sequences and the smaller corpus of the text for immediate corrections within sequences, while
with a simple PDF-to-text conversion the former would turn into common numbers that could
be confused with others in the text and the latter would be outputted in the same size as the text.
Among the different Python libraries aimed at PDF text extraction, PDFminer has been
considered the most efficient one not only for its very accurate text rendering, but also for the
possibility to directly convert the format into an XML file and the constant maintenance of the
“six” version. Despite the incorrect handling of ligatures, characters with diacritics, hyphenated
words and tabular content ([3]: 6), the library has the great advantage of being highly
customizable: to properly deliver the right order of characters as corresponding to the document
layout, the function variable LAParams() collects specific parameters that can be changed in
accordance with the structure of the text taken into consideration. In this way, it was possible to
get an XML file that preserved the characters’ position and essential information related to them
(size and font), necessary to identify the typographical features that are at the core of the
formalization method of Authorial Philology. A first look at the converted document made it

1   These considerations have been based on the critical editions of the exhamined authors. Dubious
    variants have not been taken into account for the analysis.

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A. S. Lippolis, G. Totaro – Variants Mining. Computational investigations on authorial variants:
                                                 a comparison between Leopardi and Manzoni

clear that what were superscripts and words with minor corpus in the text, in the XML file had
different sizes that have been uniformed so that no category of correction could have been missed.
Nevertheless, the major obstacle to precision concerned the beginning of a new line. In fact, as
the “textline tag” correctly identified every line of the text, it forced readings multiple lines long
to be separated every time a new line started.




Figure 1: Sample of the apparatus showing a reading multiple lines long


As a matter of fact, the first big difficulty of apparatus processing concerned the gap between
each formalized typographical representation of the text, which resulted very clear to the human
eye, as opposed to the impossibility to give a solid basis for the algorithm to understand it.
Indeed, because the readings were separated by a bigger space than the one between words —
although it did not correspond every time to the same number—, they were able to be isolated.
However, there was no key point besides an occasional hyphen to rely on when trying to
recognize when a reading was longer than one line (Figure 1). The same issue emerged when a
new page started, since even deleting the page marks would have maintained a new line. This
prevented long sequences to be recognized as one occurrence instead of multiple. The only partial
solution was to identify the hyphen between a line or another and specify in the algorithm to
delete it and consider both lines as a single reading. As for the other cases, no fix has been found.
After grouping every character into words, and the words into readings as they were on the critical
apparatus through the calculation of the gap between “bounding box” attributes, punctuation
and round brackets have been deleted as they could invalidate the regular expression patterns
that were to identify the smallest units corresponding to categories of corrections. As such, two
dictionaries have been created to improve precision in the distinguishing of single variants and
complex ones, that is to say, one with all the text contained by the tag “textline” that had at least
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one occurrence of the font dimension of the superscript, which indicated the existence of
sequences, and the other with the rest.
It was thus straightforward, after deleting punctuation and round brackets that could invalidate
our regular expression patterns with the algorithm functions clean and clean_sequences, to identify
a first pattern that matched at once the bracket, the whitespace and the word of the category of
correction. In these cases, symbols and numbers were identified as they were, while whitespace
has been represented by “\s”, with an eventual asterisk indicating when more than one could be
present, and multiple words with “\w”.
Identifying patterns of sequences was a way more complex task than that of the other categories
of correction. For instance, to isolate a reading group of three elaborations with text reuse the
pattern had to take into account all the possible combinations:
] + whitespace + 1 + words (numbers excluded) + 2 + words (numbers excluded) + → + T or 3T;
] + whitespace + 1 + words (numbers excluded) + → + 2 + words (numbers excluded) + T or 3T;
] + whitespace + 1 + words (numbers excluded) + → + 2 + words (numbers excluded) + → + T
or 3T.
Which, translated into regular expressions became:
Find_sequence_1 = re.compile(r"\]\s*1\s*([\w\s]+)\s*2([\w\s][^3]+)\s*→\s*T");
Find_sequence_2 = re.compile(r"\]\s*1\s*([\w\s]+)\s*→\s*2([\w\s]+)\s*(T|3\sT)");
Find_sequence_3 = re.compile(r"\]\s*1\s*([\w\s]+)\s*→\s*2([\w\s]+)\s*→\s*(T|3\sT)[^→]").
This process became very complex if we consider the presence of sequences with up to ten
elaboration stages.
After retrieving all the matches, the Python library Pandas was used to store all the numbers of
the frequencies in a dataframe, a two-dimensional data structure, which can then be converted
into different formats of spreadsheets to be saved locally. In this case, the two dataframes that
resulted from the algorithm —one for the results of the sequences, one for the rest of the
categories of corrections —have been saved in the Comma Separated Value (CSV) format, with
the names of the categories as columns and frequencies as values. Data has been grouped to create
a chart with the macro categories of correction and one referring to the use of text derivation in
both authors. To make the results comparable, relative frequencies have been computed for each
opera, making an average calculation of the works of reference.

       Data visualization process
Data, information and knowledge are three terms commonly used interchangeably, since they
all serve as both the input and the output of a visualization process ([11]). The huge quantity of
data available on the internet and the fact that in the last thirty years psychology has unveiled
many brain mechanisms involved in visual studies ([29]; [39]; [33]) have made visualization of
various quantities of information a dominating practice nowadays for conveying knowledge.

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                                                 a comparison between Leopardi and Manzoni

Although the purpose of data visualization is indeed to display, explore and discover information
where people can draw insight on, Yi et al. ([42]) highlight the discrepancies in literature in the
definition of the term “insight” and provide an explanation of such a process in four steps:
provide overview about the data, adjust to filter and group relevant information, detect patterns
and trends and match a mental model, that is, to reduce the distance between the data and the
user’s mental model of it. As data visualization is defined as “functional art” ([8]), in that design
is tied to the purposes of the presentation, it can be thus seen with the same traits of a technology:
a mean for an audience to help accomplish specific aims. In view of these studies, after the
algorithm of Variants Mining collected and ordered relevant data on the corrections made in the
first and second draft of I promessi sposi and Leopardi’s Canti, it was necessary to display it in a
way that made it easy to be interpreted under different points of view and help the reader
understand its patterns (see Figure 2 and Figure 3).
It was thus possible to gain a general overview on data, thanks to the various options offered by
Flourish, an open-source visualization website. Although the data distribution could have been
displayed directly from Python, the programming framework offered a narrower range of choices
than Flourish and the results lacked interactivity. For the same reasons, although RawGraphs
could have been a good representation alternative, it has not been chosen.
The first attempt at visualization concerned the representation of the categories extracted from
the algorithm, without any grouping other than the division of immediate and late sequence into
single and multiple to avoid excessive confusion in the chart. Because the categories were still too
many to gain insight on the data, an aggregate system of representation has been tried out. As A.
Cairo states, in fact, “graphics should not simplify messages. They should clarify them, highlight
trends, uncover patterns, and reveal realities not visible before” ([8]: 79). Following this principle
and Shneiderman’s Information Seeking Mantra, according to which “overview first, zoom and
filter, then details-on-demand” ([38]), another exploratory representation has been carried out,
by grouping the data in immediate and late corrections, both single and in sequence; along with
additions. Because the categories were much less, it was also possible to include relative frequency
values for each one in the visualization. Thanks to the Pyramid chart, which allows intuitive
comparison, the result is much clearer, considering that Flourish makes it possible to filter out
selected categories.
Provided that it is highly suggested ([37]) to use multiple coordinated views to represent all the
necessary information, another chart concerning the difference in categories with reuse and those
without has been developed for each work of the author. As a result, the following charts have
been developed:
    •    Macro categories of correction (immediate variants, late variants, ascriptions,
         additions);
    •    Comparison of categories with text derivation and categories without it.
In order for the analysis of Variants Mining to be publicly accessible, a Github repository with
open license has been created.


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       Case studies

Giacomo Leopardi’s Canti and Alessandro Manzoni’s I promessi sposi have been selected as case
studies to be compared. While the two works belonging to different literary genres may make it
seem that the influence of the narrative devices are decisive on the results of the work, recent
studies ([14]) show that the division between immediate and late variants do not depend upon
prose and poetry. Apart from the two authors being among the most important ones in Italian
Romanticism, what lead to their choice was also the availability of their works’ comparable
critical editions.

       Giacomo Leopardi
The illustration of the development of Criticism of Variants explored so far has been useful to
highlight the essential value of the first critical editions as they would later become the theoretical
base of Authorial Philology and, vice-versa, to show how much they served as a stimulus for the
evolution of the discipline itself.
With his almost secular history, the critical edition of Leopardi’s Canti constitutes the pivotal
work that the most recent Authorial Philology and its critical counterpart interfaced with. The
four critical editions published in Italy from the late 20’s up to 2006 witness, on the one hand,
the importance of such poetry collection in the Italian literature and, on the other hand, the
different layouts and editorial practices that were implemented to deal with the textual problems
presented in it.
The edition of Leopardi’s Canti provided by Moroncini in 1927 represents a turning point for
both the philological interest in Leopardi’s works and the new philology, because it constitutes
the first attempt at scientifically representing authorial corrections retracing the twenty-years-
long history of the text. As Moroncini himself underlined in the Proemial Discourse ([27]: LVII),
a conspicuous tradition of studies preceded its edition, showing, therefore, how the critical
interest in Leopardi’s paper-foul originated between the late XIX and the early XX century, long
before the affirmation of the criticism of variants.
Because of the few available autographs, although less remarkable than the pioneering edition by
Moroncini about the achieved results, the previous works bear evidence of the first attempts at
publishing both the handwritten and printed variants (through the graphic representation of the
autographs), and to tackle them using a critical approach.
Relying in part on these embryonic attempts, Moroncini created an indispensable tool to study
variants in Leopardi’s works. As De Robertis wrote in his commentary on the Leopardi’s Canti
“With this edition, Authorial Philology accomplishes a decisive step forward […] and
Leopardian studies enter a new dimension opened by the complete revelation of the poet’s work
around the text” ([28]: IX).
Leopardi’s manuscripts reveal his attention to detail in their appearance, which is the main
distinctive feature of his writing. While the nature of Leopardi’s works, considered as
transcriptions rather than first drafts, is well known, the many corrections and variants added by
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                                                 a comparison between Leopardi and Manzoni

the author while preparing the copy for typography, witness that the book grew over time,
progressively incorporating the poet’s ongoing meditations and stylistic experiments.
In this regard, Gavazzeni ([17]: 409-420) provided a detailed description of Leopardi’s method,
which proved fundamental to identify a steady pattern in self-emendations of the author’s
creative thinking. Furthermore, his insights helped scholars to shed light on the many corrections
and re-elaborations processes Leopardi’s poems have continuously been subjected to over the
years.
The distinctive features of each manuscript mirror the poet’s ongoing meditations, presenting
issues related to the specific poetics of which they are witnesses. This is particularly evident when
it comes to comparing the manuscripts of the Canzoni, published in 1824 in the “Neapolitan
notebook of the Idylls”. On the one hand, a series of heterogeneous elements (namely corrections,
variants, annotations, bibliographical references), comprehensively known as varia lectio, appears
on the margin of the sheet and testifies the substantial philological work that later led the author
to outline a new poetic language; on the other hand, the significant decrease of such components
in the manuscript of the Idylls allows scholars to infer the homogeneous character of these
compositions considering the whole system.
The series of Leopardi’s poems entitled Idylls appeared in its earliest extant forms in the
autograph manuscript known as “Neapolitan notebook of the Idylls”. The work consists of a
booklet with a lined page on which the author’s handwriting is clearly and sharply visible.
Written in separate phases, the poems were then corrected by the author using identifiably
different pens before being copied into Visso’s manuscript, where they were again revised.
Gavazzeni took advantage of the digital reproduction of the “Neapolitan notebook of the Idylls”.
In fact, he used it to specify all the different corrective campaigns relating to each of the three
compositional phases of the texts and did so by identifying the stratigraphy of the ink, deepening
the intuitions originally furthered by Moroncini, and then shared by Peruzzi e De Robertis.
Accordingly, four different pens have been identified, namely A, B, C, and D, which were used
to write the new texts and correct the previous ones.
The highly dynamic structure of this poetry collection is also reflected in the publishing history
of the book. Although a detailed illustration of the various reprintings is out of the scope of this
work, both a synchronic and diachronic analysis of print witnesses is fundamental because it
allows for an understanding of the overall design of a strongly unitary work. As noted above, the
textual history of Leopardi’s Canti is fascinating because much of the Italian Authorial Philology
has been based upon it. In this regard, the latest edition provided by Franco Gavazzeni constitutes
a thorough guidebook for a complete understanding of this kind of approach, for it provides
users with the critical edition of both manuscripts and printed versions, plus detailed textual
notes recording all handwritten changes, as the abovementioned notation on the different pens.

       Alessandro Manzoni
Like Leopardi’s case, the huge attention received by Alessandro Manzoni’s editions of I promessi
sposi was at the same time drive and symptom of a new phase of literary studies, when it became
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necessary to rethink about the national literary heritage and the works that conveyed a sense of
identity both politically and linguistically.
As a matter of fact, this novel was already a subject of research when it came out, starting, for
instance, from the project of linguistic comparison between the two editions of the work carried
out by Giovanni Battista De Capitani straight after the Quarantana edition got published ([35]:
21) or Gilberto Boraschi’s index of corrections relating Ventisettana and Quarantana editions
([6]). Considered the foundational text of the Italian literary tradition, I promessi sposi was indeed
the result of a deep reflection, proven at first by the long period of time in which the development
of the work had been carried out.
Manzoni’s relationship with the papers he wrote seems to mirror his own personality both in an
ethical and stylistic sense. In fact, the fast, rough and continuously renovated work of writing
carried out right after thorough reflections was counterbalanced by long periods of meditation
and a reserved character that made him reticent to public interventions. Although the author did
not leave any autobiography, he made his works talk for himself, in the context of an antiheroic
attitude that privileged the collective dimension and the pedagogical purpose not only in his
literary pieces, but even in the management of his own beloved library ([35]: 43).
Ever since the author’s early writings, literary activity has been considered ethical and centred on
the interlacement of truth, utility and beauty. However, the means to reach this theoretical
purpose were to be experimental, through confrontation in structure and language, as an inherent
dialectics between the reflexive moment and the creative one constituting a “genetic principle”
([7]: 19): not by chance all Manzoni’s most important theoretical essays follow a creative
circumstance.
In this sense, the dialogic dimension is of primary importance in the whole work of Manzoni,
not only because it is possible to witness the priority he attributed to the written word—he
composed a lot and drew very little ([35]: 17) —, but most of all, for the attention he paid to
the debates of the time and the discussions with his friends, for the interplay of mutual genesis
and influence between his works and even for the connections of his creations to the several
documents he browsed, in a dialectical perspective of knowledge acquisition and transmission
that was considered superior to the mere enunciation of facts. Accordingly, the second Parisian
stay of 1819-1820 was decisive for the maturation of the reflections that pervaded the
composition of this second tragedy and the start of I promessi sposi: Manzoni had been trying to
reach the French capital for some time, hoping to escape his political concerns that caused him
also nervous breakdowns. In such a cultural turmoil, Walter Scott’s Ivanhoe was a ground-
breaking work for the liberal intellectual circle near Claude Fauriel. At the time, the novel was
becoming widespread in France, in an environment of reevaluation of history as a mean, along
with philosophy, to fight the French absolutism. According to Augustin Thierry’s review of the
novel, for the first time the events were focused on the reactions of individuals to the major social
and national circumstances, no more on the private passions of single characters.
It is not by chance, then, that Manzoni chose to follow an analogous path when he realized the
problems of Adelchi and decided to begin Fermo e Lucia (a title derived from a reference of Ermes
Visconti in a letter to Gaetaneo Cattaneo, but most likely it was Gli sposi promessi, as shown by
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                                                 a comparison between Leopardi and Manzoni

[24]), at a time of rise of Italian riots for the independency from the Austrian domain, two years
after the cancellation of the review Conciliatore and the incarceration in 1821 of his director,
Silvio Pellico.
Although it is a first draft and was never published during the life of Manzoni, Fermo e Lucia is
a complete and definite work that must not be considered as subordinate to its best known
revision. Organized in thirty-seven chapters, written between April 24, 1821 and September 17,
1823 according to the two dates that can be found at the beginning and the end of the text, the
autograph allows to understand the way Manzoni worked and conceived his novel. It is, first of
all, a “pure modern invention” ([30]: 586) that represents real life in the shape of both historical
events and the everyday world of private matters doomed to be left behind, thus worth to “live
within it” ([15]: 352-353) and to be narrated to a potentially wide public. It is not only a first
step towards the democratization of literature, but also the first attempt at opening the path to
the realist frontier of the novel, with a focus on how the major events of history have impacted
on the people of smaller and forgotten realities ([30]: 5).
Although the difference between Fermo e Lucia and the Ventisettana was well-known, making
the first draft to be considered as an autonomous text, even if unrefined under many points of
view, the need to discern and untangle the interventions related to the second draft from those
successive to the writing of the Fermo e Lucia were equally as recognized, but never carried out
in a complete way before the 2012 edition ([31]).
Despite its huge number of interventions, the second draft of I promessi sposi had in fact always
been considered as subordinate to its printed counterpart, which shares the same narrative
structure with, unlike the first and second draft. Instead, it is a necessary document to understand
the development of Manzoni’s reflection on the relationship between language, truth of the story
and truth of the art, especially because of the reuse of the pages of the first draft’s first tome,
which underwent an intense re-elaboration.
In this perspective, the first eight chapters for the first and the second draft has been chosen as a
sample for the Variants Mining analysis because they were comparable on the one hand, but on
the other they witnessed a substantial development in the author’s creative process.




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       Leopardi and Manzoni: a comparison between two working
       methods




Figure 2: Comparison between macro categories of correction in Leopardi and Manzoni's works (average
of the relative frequencies of the selected works)




Figure 3: Comparison between categories with or without reuse in Leopardi and Manzoni's works (average
of the relative frequencies of the selected works)


The analysis carried out on the chosen examples marks a clear difference between the two
authors. As shown in Figure 2, while Leopardi’s average frequency of corrections is quite
unevenly distributed, Manzoni’s drafts seem to have more balance in distribution. The high
prevalence of late corrections in Leopardi’s selected works clearly shows how his working method
differs from Manzoni’s. In fact, following the already mentioned pioneering study of Italia ([22]),
which considers Leopardi a writer “by map”, as he had a specific planning for his compositions,
the many late corrections, notes, glosses, annotations, and variants visible in his papers are the
most truthful testimony of the effort to achieve what the author calls “minute perfection”
(“minutissima perfezione”): it arises from a profound faith in the word as truth, understood not
as a mere sign of communication but as an ontological entity, characterized by its physicality.
On the other hand, the elevate number of immediate variants shown in Manzoni’s papers induces
to think about a method of correction “by compass”, as from the confusion of the papers it is
clear the author did not have a preconceived plan for his composition, but rather imposed the
draft a definitive character that did not belong to it, where his reflections had to gradually focus
on the details through prompt corrections despite ignoring what the final text would be. As a
result, in the manuscripts of the author it is possible to witness a spontaneous dialogic proceeding
of the thought rather than an established intention both in content and language ([35]: 17).

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                                                 a comparison between Leopardi and Manzoni

A common aspect between both two writers is the low incidence of additions. As it is evident
from Figure 3, Leopardi’s works are characterized by the prevalence of categories that entail reuse
of the previous text, rather than being an innovation. In the case of Manzoni, the data can be
motivated by Giovanni Nencioni’s statement, according to whom “the changes made by
Manzoni are not innovations that cut a weave and a tone essentially aulic, but touch-ups of
adjustment and levelling on a weave and tone fundamentally common already at the beginning”
([32]: 241). A quantitative content analysis of the apparatus could shed light on this category’s
lexical diversity with respect to the remaining text and confirm or disprove these theses.
For what concerns Figure 3, reuse of previous text constitutes the key point to really understand
the peculiarities of the two different approaches to the act of writing. In fact, Leopardi’s
interventions turn out to be strictly influenced by formal constraints that characterize poetry and
in particular by the search for a pleasant musicality of the verse and by compensatory techniques
due to the introduction of innovative metric solutions adopted by the author, such as the canzone
libera.
On the contrary, in Manzoni’s case immediate corrections without any text derivation are in
clear prevalence, proving once again that the author’s thought process acted immediately and
without a precise direction in mind. It is thus evident from the chart that he tried to concretize
and shape his thoughts in the very moment of textual composition, resulting in a high majority
of immediate corrections without text reuse that outnumber all the others. Therefore, the
obtained data allow to hypothesize an influence of the different narrative devices, namely prose
and poetry, on the two authors’ elaboration processes, that are on the one hand the mechanisms
of the description and both the meter and musicality on the other.
Furthermore, the data also shows that due to the prevalence of immediate variants without reuse,
the second draft of I promessi sposi, which is included in one of the works that make up the
average output of the results, can be considered as a manuscript written in one go like the first
one. As a matter of fact, both first and second draft are tendentially written right away, but
despite knowing it needed further adjustments, Manzoni considered Fermo e Lucia as a text that
had to be autonomous. Despite the complete status of the draft and the reuse of some of its parts
in the second draft, what had to change was created ex novo.



       Future developments

As already underlined, one of the primary purposes that were set at the beginning of this work
was to extract the information contained in the apparatus directly from the PDF of the reference
editions due to the almost total absence, in the panorama of critical digital editions, of
experiments in the field of Authorial Philology.
However, the potential of the implications resulting from the analysis of an author’s correction
categories can expand well beyond the essential, but traditional literary criticism. In fact, this
study was born in the wake of the conviction that corrections should be considered the author’s
fingerprints, i.e., responding to his general attitude towards artistic creation.
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As such, the Variants Mining algorithm can also be helpful for the study of authorship
attribution, as it is based on the consistent occurrence of specific features in a corpus of texts.
More so, when considering the direct extraction of frequencies from the critical apparatus of
Authorial Philology, as it accounts for elaboration phases that can also involve multiple lines of
texts instead of comparing single terms’ rate of variation. In fact, recent studies highlight the
importance in authorship attribution detected through machine learning techniques not to
consider only word-level features, which can be misleading when trying to detect forgery, but
also syntactic elements, as they indicate the writers’ way to construct their texts and are more
difficult to fake, especially in multi-author documents ([43]). In this regard, Chaski ([10])
suggests that syntactic features are less common in authorship attribution because of the difficulty
to extract such information with precision. However, the critical apparatus already provides
information at this level so that it is not necessary to involve complex but less precise
computational studies.
At the same time, researchers have recently been trying new ways to capture this kind of
information, such as Kim et al. with a k-embedded-edge subtree ([25]); Tshuggnall and Specht
([40]) with syntax trees or the more traditional dependency grammars ([13]), making it possible
to even combine information of the critical apparatus with a more and more granular
identification of syntactic structures. Another advantage of Variants Mining in this field of
research would thus concern the fact there is no need to necessarily encode the text and its
variants to obtain a complete analysis for authorship attribution, but rather to perform the same
algorithm on both the reference texts and their corresponding critical apparatus and consequently
draw conclusions on their comparison.
Among the various innovative elements that characterize the method proposed in this work, the
study of the critical apparatus based on the way corrections are made, rather than on their
content, certainly represents the richest implications in terms of theoretical potential. In this
context, the study on late style theory can be a fruitful research field to understand whether it
can be supported with empirical evidence. If late style is “a distinctive signature that characterizes
the end of a career, as the contours of the aging body are mapped onto the weave of writing”
([34]: 147), this change should also reverberate on the way an author corrects their texts. In it
being a peculiar approach to authorship, not as something static but rather as a process of change,
“late style” seems rather fitting to the study of authorial variants, as Contini, when facing the
problem of the meaning of a study of variants, defined the text itself as a process whose dynamism
has to be taken into consideration when dealing with it in a critical way.
Apart from widening the sample corpus to the entire work of the author, a comparative study of
the correction methodologies, implemented by expanding the study carried out in this research
project, could allow to investigate the presence of similar correction patterns even among very
different authors, both in terms of age and field of action.
As it has been already underlined, despite the ecdotic development of Authorial Philology has
reached a very high level, especially in the Italian context, it has remained confined to the separate
study of individual authors, effectively preventing a comparative study of the authors’
compositional and correcting methods (see [5]: 263-264). Accordingly, the extraction of data
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A. S. Lippolis, G. Totaro – Variants Mining. Computational investigations on authorial variants:
                                                 a comparison between Leopardi and Manzoni

from digital critical editions annotated from the PDF of the text or its TEI encoded version
allows to extend the analysis to authors outside the Italian context to verify how the dynamics of
correction change in different eras and in the texts of authors who reference to areas of knowledge
that are also external to the strictly literary one such as the scientific, historical or philosophical
one.
The taxonomic categorization of the phenomenology of corrections and their analytical analysis
made possible through the proposed methodology could, therefore, contribute to delineate a
general theory of corrections: this would allow to consider the concept of creativity from a
different perspective, providing empirical evidence that emphasizes its inevitable material and
time-dependent premises, discarding the notion of the modern manuscripts as products of the
authors’ genius ever since the Enlightenment.
Moreover, it must be emphasized that this study aims to configure itself as state of the art in a
moment of fundamental transition towards a born-digital literature and the development of
archives of digital native texts, such as the very recent ALDiNa, a project born under the aegis of
Associazione per l’Informatica Umanistica e la Cultura Digitale, which aims to guarantee
adequate documentation and enhancement of the authorial digital native.
The attention to the philological dimension therefore becomes fundamental to ensure respect
for the author’s last will in a context, that of the digital, which accentuates the fluidity of the text
and its ephemeral character.
Therefore, starting from these premises, the approach of the proposed methodology emerges
evidently in an anthropological sense, testifying on corrective methodologies of the past while
the study of author variants is inevitably moving towards new practices.



       Conclusion

A panoramic analysis of the most recent projects developed in the field of digital philology clearly
showed how the digital turn has led to a real methodological revolution in philological research.
However, the scholars' attempts were mainly aimed at exploiting digital infrastructures to
simplify the use of critical apparatuses thanks to the possibility of publishing all the witnesses,
thus focusing on the content of the corrections rather than on the way in which they are made.
This paper aims to fill this gap by providing an innovative technique able to deepen the
conventional philological readings relying on the one hand on the solid theoretical infrastructure
provided by the authorial philology and its critical counterpart, namely the Criticism of Variants,
and on the other on the potential of computational and data visualization tools that allow to
intuitively understand the obtained data in a more immediate and effective way.
Although pursued thanks to the aid of automatic and quantitative methods, this study’s scope is
ultimately rooted in literary criticism because it aims to provide evidence-based analysis that
participates in the long-lasting debate on creativity by emphasizing the active role played by

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authorial corrections in better defining the mechanisms underlying the author’s creative
thinking.
The analysis carried out on the chosen case-study, namely Manzoni and Leopardi’s samples of
writing, has revealed important feature of their working method: in particular, the focus on the
correction categories allowed to highlight that differences in the elaboration processes are likely
to mirror differences in the authors’ intellectual disposition such as Manzoni's tendency to
proceed by gradual focusing on the object and Leopardi's aptitude to return to the texts at a later
time to perfect them.
Moreover, it seems possible to hypothesize that the prevalence of authorial interventions
characterized by some reuse of the previous text are determined by some constraints of the poetic
texts that also are peculiar of Leopardi’s style, such as the attention to the musicality of the verse
and the not always linear relationship between meter and syntax.
These results made it clear that the automatic detection of correction patterns must be developed
even further. By expanding this study to as many authors as possible, Variants Mining would
make it possible to write a grammar of correction which all the different approaches to the act of
writing could be referred to.



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