Darwin’s Semantic Voyage

The preprint of my project “Exploration and Exploitation of Victorian Science in Darwin’s Reading Notebooks” was released on arXiv on Friday. The paper is joint work with my advisors Colin Allen and Simon DeDeo.

This has consumed my life for the past year and I’m incredibly proud of the results. It’s an entertaining read — printing pages “1-11,24-28” gives the main body and references. 12-23 are the “supporting information” explaining some of the archival work, mathematics, and model verification, but absolutely not central to the key points of the paper.

The key point for digital humanities is that we’ve come up with a way to characterize an individual’s reading behaviors and identify key biographical periods from their life. Darwin is incredibly well-studied, so our results largely confirm existing history of science work. However, by adjusting the granularity we can also suggest hypotheses for further investigation – in this case, the period of Darwin’s life from 1851-1853 after his daughter’s death. For less well-studied individuals, this may help humanists gain traction on narrative organization when interacting with large historical archives.

The key point for cognitive scientists is that we can now characterize information foraging behaviors on multiple timescales using an information theoretic measure of cognitive surprise. While many people have studied foraging behavior in individuals on the order of minutes, or in cultures on the order of decades – this is the first study that looks at how an individual interacts with the products of their culture over the course of a lifetime.

It’s important to note that we don’t say anything about how his reading affected his writing – that’s for paper #2!

Also, I’ll presenting this work at the 2015 Conference on Complex Systems this Friday at Arizona State University, with slides available on Google Slides.

Exploration and Exploitation of Victorian Science in Darwin’s Reading Notebooks
Jaimie Murdock, Colin Allen, Simon DeDeo
Abstract: Search in an environment with an uncertain distribution of resources involves a trade-off between local exploitation and distant exploration. This extends to the problem of information foraging, where a knowledge-seeker shifts between reading in depth and studying new domains. To study this, we examine the reading choices made by one of the most celebrated scientists of the modern era: Charles Darwin. Darwin built his theory of natural selection in part by synthesizing disparate parts of Victorian science. When we analyze his extensively self-documented reading we find shifts, on multiple timescales, between choosing to remain with familiar topics and seeking cognitive surprise in novel fields. On the longest timescales, these shifts correlate with major intellectual epochs of his career, as detected by Bayesian epoch estimation. When we compare Darwin’s reading path with publication order of the same texts, we find Darwin more adventurous than the culture as a whole.