The Development of Darwin's Origin of Species

TL;DR

This study uses topic modeling on Darwin's reading notes and manuscripts to analyze his intellectual development, publication delays, and the relationship with Wallace, providing quantitative insights into historical scientific processes.

Contribution

It applies a novel reading model to Darwin's documents to quantitatively investigate historical questions about his delay in publishing and his interactions with Wallace.

Findings

Confirmed external pressures influenced Darwin's publication delay.

Identified the relationship between Darwin and Wallace's theories.

Dated the 'Outline and Draft' as preceding the 1842 essay.

Abstract

From 1837, when he returned to England aboard the $\textit{HMS Beagle}$, to 1860, just after publication of $\textit{The Origin of Species}$, Charles Darwin kept detailed notes of each book he read or wanted to read. His notes and manuscripts provide information about decades of individual scientific practice. Previously, we trained topic models on the full texts of each reading, and applied information-theoretic measures to detect that changes in his reading patterns coincided with the boundaries of his three major intellectual projects in the period 1837-1860. In this new work we apply the reading model to five additional documents, four of them by Darwin: the first edition of $\textit{The Origin of Species}$, two private essays stating intermediate forms of his theory in 1842 and 1844, a third essay of disputed dating, and Alfred Russel Wallace's essay, which Darwin received in 1858. We address three historical inquiries, previously treated qualitatively: 1) the mythology of "Darwin's Delay," that despite completing an extensive draft in 1844, Darwin waited until 1859 to publish $\textit{The Origin of Species}$ due to external pressures; 2) the relationship between Darwin and Wallace's contemporaneous theories, especially in light of their joint presentation; and 3) dating of the "Outline and Draft" which was rediscovered in 1975 and postulated first as an 1839 draft preceding the Sketch of 1842, then as an interstitial draft between the 1842 and 1844 essays.