David Ranzolin

### Introduction

When I was in grad school at Emory, I had a favorite desk in the
library. The desk wasn't particularly cozy or private, but what it
lacked in comfort it made up for in real estate. My books and I needed
room to operate. Students of the ancient world require many tools, and
when jumping between commentaries, lexicons, and interlinears,
additional clutter is additional "friction", i.e., lapses in thought due
to frustration. Technical solutions to this clutter exist, but the best
ones are proprietary and expensive. Furthermore, they are somewhat
inflexible, and you may have to shoehorn your thoughts into their
framework. More friction.

Interfacing with [the Perseus Digital
Library](https://www.perseus.tufts.edu/hopper/) was a popular online
alternative. The library includes a catalog of classical texts, a Greek
and Latin lexicon, and a word study tool for appearances and references
in other literature. If the university library's reference copies of
BDAG^[1](#fn:1){.footnote-ref role="doc-noteref"}^ and *Synopsis
Quattuor Evangeliorum*^[2](#fn:2){.footnote-ref role="doc-noteref"}^
were unavailable, Perseus was our next best thing.

Fast forward several years, and I've abandoned my quest to become a
biblical scholar. Much to my father's dismay, I've learned writing code
is more fun than writing exegesis papers. Still, I enjoy dabbling with
dead languages, and it was the desire to wed my two loves, biblical
studies and R, that birthed my latest package, `rperseus`. The goal of
this package is to furnish classicists with texts of the ancient world
and a toolkit to unpack them.

### Exploratory Data Analysis in Biblical Studies

Working with the Perseus Digital Library was already a trip down memory
lane, but here's an example of how I would have leveraged `rperseus`
many years ago.

My best papers often sprung from the outer margins of my [*Nestle-Aland
Novum Testamentum
Graece.*](https://en.wikipedia.org/wiki/Novum_Testamentum_Graece) Here
the editors inserted cross references to parallel vocabulary, themes,
and even grammatical constructions. Given the intertextuality of
biblical literature, the margins are a rich source of questions: Where
else does the author use similar vocabulary? How is the source material
used differently? Does the literary context affect our interpretation of
a particular word? This is exploratory data analysis in biblical
studies.

Unfortunately the excitement of your questions is incommensurate with
the tedium of the process--EDA continues by flipping back and forth
between books, dog-earring pages, and avoiding paper cuts. `rperseus`
aims to streamline this process with two functions: `get_perseus_text`
and `perseus_parallel`. The former returns a data frame containing the
text from any work in the Perseus Digital Library, and the latter
renders a parallel in `ggplot2`.

Suppose I am writing a paper on different expressions of love in Paul's
letters. Naturally, I start in 1 Corinthians 13, the famed "Love
Chapter" often heard at weddings and seen on bumper stickers. I finish
the chapter and turn to the margins. In the image below, I see
references to Colossians 1:4, 1 Thessalonians 1:3, 5:8, Hebrews
10:22-24, and Romans 8:35-39.

![](/img/blog-images/2017-12-05-rperseus/nantg.png)*1 Corinithians 13 in
Nestle-Aland Novum Testamentum Graece*

Ignoring that some scholars exclude Colossians from the "authentic"
letters, let's see the references alongside each other:

::: {.highlight}
``` {.chroma tabindex="0"}
library(rperseus) #devtools::install_github(“ropensci/rperseus”)library(tidyverse)tribble(  ~label, ~excerpt,  "Colossians", "1.4",  "1 Thessalonians", "1.3",  "1 Thessalonians", "5.8",  "Romans", "8.35-8.39"  ) %>%   left_join(perseus_catalog) %>%  filter(language == "grc") %>%  select(urn, excerpt) %>%  pmap_df(get_perseus_text) %>%  perseus_parallel(words_per_row = 4)
```
:::

![](/img/blog-images/2017-12-05-rperseus/Parallel1.png)

A brief explanation: First, I specify the labels and excerpts within a
tibble. Second, I join the lazily loaded `perseus_catalog` onto the data
frame. Third, I filter for the Greek^[3](#fn:3){.footnote-ref
role="doc-noteref"}^ and select the columns containing the arguments
required for `get_perseus_text`. Fourth, I map over each urn and
excerpt, returning another data frame. Finally, I pipe the output into
`perseus_parallel`.

The key word shared by each passage is *agape* ("love"). Without going
into detail, it might be fruitful to consider the references alongside
each other, pondering how the semantic range of *agape* expands or
contracts within the Pauline corpus. Paul had a penchant for
appropriating and recasting old ideas--often in slippery and unexpected
ways--and your Greek lexicon provides a mere approximation. In other
words, how can we move from the dictionary definition of *agape* towards
Paul's unique vision?

If your Greek is rusty, you can parse each word with `parse_excerpt` by
locating the text's urn within the `perseus_catalog` object.

::: {.highlight}
``` {.chroma tabindex="0"}
parse_excerpt(urn = "urn:cts:greekLit:tlg0031.tlg012.perseus-grc2", excerpt = "1.4")
```
:::

| word   | form       | verse | part_of_speech | person | number   | tense  | mood       | voice  | gender    | case       | degree |
|:-------|:-----------|:------|:---------------|:-------|:---------|:-------|:-----------|:-------|:----------|:-----------|:-------|
| ἀκούω  | ἀκούσαντες | 1.4   | verb           | NA     | plural   | aorist | participle | active | masculine | nominative | NA     |
| ὁ      | τὴν        | 1.4   | article        | NA     | singular | NA     | NA         | NA     | feminine  | accusative | NA     |
| πίστις | πίστιν     | 1.4   | noun           | NA     | singular | NA     | NA         | NA     | feminine  | accusative | NA     |
| ὑμός   | ὑμῶν       | 1.4   | pronoun        | NA     | plural   | NA     | NA         | NA     | masculine | genative   | NA     |

If your Greek is *really* rusty, you can also flip the `language` filter
to "eng" to view an older English translation.^[4](#fn:4){.footnote-ref
role="doc-noteref"}^ And if the margin references a text from the Old
Testament, you can call the Septuagint as well as the original
Hebrew.^[5](#fn:5){.footnote-ref role="doc-noteref"}^

::: {.highlight}
``` {.chroma tabindex="0"}
tribble(  ~label, ~excerpt,  "Genesis", "32.31",  "Genesis, pointed", "32.31",  "Numeri", "12.8",  "Numbers, pointed", "12.8"  ) %>%   left_join(perseus_catalog) %>%  filter(language %in% c("grc", "hpt")) %>%  select(urn, excerpt) %>%  pmap_df(get_perseus_text) %>%  perseus_parallel()
```
:::

![](/img/blog-images/2017-12-05-rperseus/Parallel2.png)

Admittedly, there is some "friction" here in joining the
`perseus_catalog` onto the initial tibble. There is a learning curve
with getting acquainted with the idiosyncrasies of the catalog object. A
later release will aim to streamline this workflow.

### Future Work

[Check the
vignette](https://docs.ropensci.org/rperseus/articles/rperseus-vignette.html)
for a more general overview of `rperseus`. In the meantime, I look
forward to getting more intimately acquainted with the Perseus Digital
Library. Tentative plans to extend `rperseus` a Shiny interface to
further reduce "friction" and a method of creating a "book" of custom
parallels with `bookdown`.

### Acknowledgements

I want to thank my two rOpenSci reviewers, [Ildikó
Czeller](https://www.ildiczeller.com/) and [François
Michonneau,](https://francoismichonneau.net/) for coaching me through
the review process. They were the first two individuals to ever
scrutinize my code, and I was lucky to hear their feedback. rOpenSci
onboarding is truly a wonderful process.

::: {.footnotes role="doc-endnotes"}

------------------------------------------------------------------------

1.  ::: {#fn:1}
    Bauer, Walter. *A Greek-English Lexicon of the New Testament and
    Other Early Christian Literature.* Edited by Frederick W. Danker.
    3rd ed. Chicago: University of Chicago Press,
    2000. [↩︎](#fnref:1){.footnote-backref role="doc-backlink"}
    :::

2.  ::: {#fn:2}
    Aland, Kurt. *Synopsis Quattuor Evangeliorum.* Deutsche
    Bibelgesellschaft, 1997. [↩︎](#fnref:2){.footnote-backref
    role="doc-backlink"}
    :::

3.  ::: {#fn:3}
    The Greek text from the Perseus Digital Library is from 1885
    standards. The advancement of textual criticism in the 20th century
    led to a more stable text you would find in current editions of the
    Greek New Testament. [↩︎](#fnref:3){.footnote-backref
    role="doc-backlink"}
    :::

4.  ::: {#fn:4}
    The English translation is from Rainbow Missions, Inc. *World
    English Bible.* Rainbow Missions, Inc.; revision of the American
    Standard Version of 1901. I've toyed with the idea of incorporating
    more modern translations, but that would require require resources
    beyond the Perseus Digital Library. [↩︎](#fnref:4){.footnote-backref
    role="doc-backlink"}
    :::

5.  ::: {#fn:5}
    "hpt" is the pointed Hebrew text from *Codex
    Leningradensis.* [↩︎](#fnref:5){.footnote-backref
    role="doc-backlink"}
    :::
:::


Introduction   When I was in grad school at Emory, I had a favorite desk in the library. The desk wasn’t particularly cozy or private, but what it lacked in comfort it made up for in real estate. My books and I needed room to operate. Students of the ancient world require many tools, and when jumping between commentaries, lexicons, and interlinears, additional clutter is additional “friction”, i.e., lapses in thought due to frustration.

Messaggi di Rogue Scholar

Exploratory Data Analysis of Ancient Texts with rperseus