Evidence of Intertextuality: Investigating Paul the Deacon's Angustae Vitae

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Evidence of Intertextuality:
Investigating Paul the
Deacon’s
Angustae Vitae
Forstall, C. W.
forstall@buffalo.edu
Department of Classics, State University of
New York at Buffalo
Jacobson, S.L.
slj25@buffalo.edu
Department of Classics, State University of
New York at Buffalo
Scheirer, W. J
wjs3@vast.uccs.edu
Department of Computer Science, University of
Colorado at Colorado Springs
The study of intertextuality, the shaping of
a text’s meaning by other texts, remains a
laborious process for the literary critic. Kristeva
(Kristeva, 1986) suggests that "Any text is
constructed as a mosaic of quotations; any
text is the absorption and transformation of
another.& The nature of these mosaics is widely
varied, from direct quotations representing
a simple and overt intertextuality, to more
complex transformations that are intentionally
or subconsciously absorbed into a text. The
burden placed upon the literary critic to verify
suspected instances of intertextuality is great.
The critic must reference a large corpus of
possible contributing works, and thus must
often be familiar with more texts than was the
author whom they are studying. Since, in many
cases, the problem is one of pattern recognition,
it is a good candidate for automated assistance
by computers.
In this work, currently in progress, we
propose the use of machine learning and
related statistical methods to improve the
process by which intertextuality is studied.
Specifically, we are working with instances
where an author has knowledge of particular
texts, and reflects this in discrete passages
within their own work. These intertexts may
comprise fragmentary quotations, paraphrases,
or even stylistic similarity. A passage may
be reminiscent of a particular author, or of
a particular literary group. We have defined
three different classes of style markers to
verify intertexts: phonetic, metric, and dictional.
To evaluate the proposed style markers and
classification methods, we have chosen an
intriguing case study: Paul the Deacon’s 8th
century poem
Angustae Vitae
(Paul the Deacon,
1881), which we suggest has a strong connection
to first-century Neoteric poetry.
Our earlier work in authorship and stylistic
analysis (Forstall and Scheirer, 2009) has
considered the importance of phonetic style
markers, with the observation that sound
plays a fundamental role in an author’s
style, particularly for poets. To capture sound
information, we have developed a feature that
we call a
functional n-gram
, whereby the
power of the Zipfian distribution is realized by
selecting the n-grams that occur most frequently
as features, while preserving their relative
probabilities as the actual feature element. By
using more primitive, sound-oriented features,
namely, character- and phoneme-level n-grams,
we are able to build accurate classifiers with
the functional n-gram approach. We have used
two different classification algorithms with
functional n-grams, yielding very promising
results. The first method, a traditional SVM
learning approach based on the work of
Diederich et al. (Diederich et al., 2003),
distinguished authors of Latin poetry with
98.75% accuracy. The second method, a PCA
clustering approach (Holmes et al., 2001),
showed distinct stylistic separation between the
Homeric poems. In light of our previous work,
we know that phonetics is an important tool
for verifying intertexts, for the same reason it
was important for poetics — repetitive sound
distinguishes style.
Following this idea of repetitive sound further,
we use meter as an additional style marker.
For strict meters, it is straightforward to
identify their type by analyzing the weights
of the syllables in a line. In practice, the
nuance of particular poets, or groups of poets,
creates unique variations in meter, giving us
a discriminating feature. By including meter
as another dimension in the feature vector of
the SVM learning for the functional n-grams
described above, we enhance the discriminatory
power of the resulting classifiers. It remains
an open question in our work whether meter

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alone is powerful enough to achieve the same
classification results for individual authors as
the functional n-gram. Its utility for group
classification is more apparent.
Pulling back from sound, we have also developed
a style analysis for diction that is somewhat
the opposite of the functional n-gram approach.
Considering the Zipfian distribution once again,
we turn to elements that occur with lower
probabilities. The power of functional n-grams
relies on the amount of information carried
by the elements at the left side of the Zipfian
distribution (assuming the
x
axis is organized
from most frequent to least frequent). For
this new style marker, we desire something
that is the opposite of functional—features that
occur infrequently, but not necessarily
hapax
legomena
.
Thus, we fix a desired probability range for
words that occur infrequently, and look for n-
gram sequences composed of only those words
in a particular passage, ignoring all others:
(P
low
< Pr(word
1
) < P
high
) ... (P
low
< Pr(word
2
) <
P
high
) ... (P
low
< Pr(word
n
) < P
high
) (1)
where n ≥ 3. The probability of the resulting n-
gram is compared to pre-computed probabilities
of the same n-gram (should it exist) for specific
authors, or literary groups. This type of style
marker is very well suited to our case study,
where certain word sequences are common to
a particular group (the Latin Neoterics), but
uncommon or non-existent in the work of other
groups.
With our style markers in hand, we turn to our
case study. In
Angustae Vitae
, Paul the Deacon
opposes poetic inspiration and production in
the classical world with the writing of poetry
in the Christian monastic context. Although
he posits the classical and monastic worlds
as opposites, the use of Catullan diction and
models of poetic exchange recalls the paradigm
of the Neoteric, proto-elegiac lover, his beloved,
and his poetological concerns. This model is
recontextualized to reflect monastic love and
poetic exchange. The source of inspiration
remains the same — love — but there is a new
beloved and a new Muse. While he avoids saying
he directly imitates his classical predecessors,
Paul the Deacon’s poetry is peppered with
classical intertexts. Not all of these intertexts are
purposeful allusions. However, it is clear that he
was at least well-versed in the poetry of Horace,
Virgil, and Ovid. Thus, it becomes our task to
verify the portions of the poem believed to be
inspired by Catullus.
Further study of the Catullan manuscript
tradition and Paul the Deacon’s life would be
necessary to prove his knowledge of Catullus
conclusively. This work will proceed from the
a priori
conclusion that Paul the Deacon had
read Catullus. This conclusion is based on the
abundance of intertexts and the crucial role
they play in coloring Paul the Deacon’s poetry.
We can gain a sense of these intertexts we are
examining by looking at a particular instance.
As the poem opens, the Muses, who have
found the cloistered life not of their liking,
have abandoned the narrator. More precisely,
the Muses are fleeing the fellowship of the
cloistered life,
angustae vitae fugiunt consortia
Musae
. Thus, there is an opposition: the
consortia angustae vitae versus the Musae
— the fellowship of monastic life versus the
classical relationship of the poet and Muses.
This opposition continues in lines 2 — 3. The
Muses do not wish to live in the fenced-in
gardens of monasteries, but rather they desire
to play in rosy meadows,
claustrorum septis nec
habitare volunt, / per rosulenta magis cupiunt
sed ludere prata
. Here,
septa
, the cultivated,
enclosed garden of a monastery, is contrasted
with the
rosulenta prata
, a wild, open meadow.
These opening lines may reference Eclogue
1 of Vergil, but reading them with Catullus
provides a richer understanding of the themes
of the poem. Indeed, what the Muses desire
in
Angustae Vitae
are cornerstones of Catullan
diction. Lines 2 — 3 recall the opening lines
of Catullus 2. The Muses desire to play in
fields (
cupiunt sed ludere prata
) and to tend to
(
colunt
) their delights (
delicias
), just as Catullus’
girlfriend is accustomed to play (
ludere solet
)
with her own pet/delight (
deliciae
). The classical
Muses are compared with the poet’s beloved.
These are the Muses of elegiac love.
Ludere
,
furthermore, is a by-word in Catullus for the
production of poetry.
By taking into consideration all such intertext
candidates in
Angustae Vitae
, we will show
that machine classification is able to produce
statistically strong validation results. We

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present our study of the three style markers
in this context, highlighting strengths and
weaknesses. We hope that this case study will
serve as a first step towards a more sophisticated
and efficient analysis of intertextuality in
general. Moreover, this work raises important
linguistic questions on the nature of conscious
and subconscious influence in style, which is an
area we intend to explore in further work.
References
Diederich, J., Kindermann, J., Leopold,
E. and Paass G.
(2003). 'Authorship
Attribution with Support Vector Machines'.
Applied Intelligence.
19(1-2)
: 109-123.
Forstall, C.W. and Scheirer, W.J.
(2009).
'Features from Frequency: Authorship and
Stylistic Analysis Using Repetitive Sound'.
Chicago Colloquium on Digital Humanities and
Computer Science.
Chicago.
Holmes, D., Robertson, M., and Paez,
R.
(2001). 'Stephen Crane and the New York
Tribune: A Case Study in Traditional and Non-
traditional Authorship Attribution'.
Computers
and the Humanities.
35(3)
: 315—331.
Kristeva, J.
(1986). 'Word, Dialogue and
Novel'.
The Kristeva Reader.
Moi, T. (ed.). New
York: Columbia University Press, pp. 34—61.
Paul the Deacon
(1881). 'Carmina'.
Monumenta Germaniae Hisotica, Poeta Latini
Aevi Carolini Vol 1.
Diemmler, E. (ed.). Berlin.